fix(social): robot blocks

Blocking an auto-match opponent who is secretly a pooled robot is recorded  instead in a separate `robot_blocks` table.

Now blocking behaves the same in that game (struck name, hidden composer) and lists the blocked opponent under the name you saw, but is recorded only against that game — the disguise holds, the shared robot is never globally blocked, and the matchmaker keeps pairing you with robots (so you can never block yourself out of opponents).

- the shared robot account is never put in `blocks`
- the matchmaker keeps it free and it is not blocked under its other per-game names
- the blocked list and the in-game card still show it by joining that table; an unblock deletes the row

PRERELEASE.md

@@ -35,7 +35,7 @@ the edge before prod. Each phase maps back to the owner's raw pre-release TODO l
 | AD | Advertising banner ("ad network"): server-driven weighted campaigns (percent weight + validity window; the perpetual default fills the remainder up to 100%), bilingual messages shown by bot (`service_language`); eligibility = free account + empty hint wallet + no `no_banner` role (guests included); the resolved feed rides `profile.get` with a `notify` `banner` re-poll on eligibility change; `/_gm/banners` admin + global display timings; client smooth-weighted-round-robin rotation + fade-out/gap/fade-in UX. A single `app.load` bootstrap aggregator was considered and **deferred** (see ARCHITECTURE §10). | owner ad-hoc | **done** (PR1 backend+admin, PR2 UI rotation) |
 | GL | Simultaneous quick-game cap (10): grey "New Game" + a lobby notice at the cap; backend gate on quick enqueue + invitation creation (409 `game_limit_reached`), accepting invitations exempt; `at_game_limit` rides `games.list` | owner ad-hoc | **done** |
 | CR | In-game chat read receipts: per-message `unread_seats` bitmask (migration `00008`); a per-viewer unread **dot** in the lobby + game header (a nudge counts and clears when its recipient moves); reading = opening the move history (the 💬 fade-blinks twice) or the chat, acked (`chat.read`) only when unread; `chat_read_duration` + `chat_unread_messages` metrics + tracing + the **Scrabble — Messages** Grafana dashboard (follow-up PR); a message to a disguised robot opponent is born read; admin unread-only filter / read column / per-seat read card | owner ad-hoc | **done** |
-| BX | Asymmetric per-user block + in-game controls: a block now silently suppresses everything **from** the blocked user (chat, nudge, friend requests, invitations are kept but never delivered/surfaced, born-read) while they notice nothing, **without** deleting the friendship (unblock restores it); auto-match excludes a block-related pair (either direction); in-game opponent card gains a ✖️ **block** control (mirroring 🤝, red "Block?" confirm, mutual-hide, struck name + hidden chat composer when blocked); optimistic apply + `user_blocked`/`user_unblocked` event confirm + rollback; admin user card gains **blocks / blocked-by / friends** cross-linked lists | owner ad-hoc | **done** |
+| BX | Asymmetric per-user block + in-game controls: a block now silently suppresses everything **from** the blocked user (chat, nudge, friend requests, invitations are kept but never delivered/surfaced, born-read) while they notice nothing, **without** deleting the friendship (unblock restores it); auto-match excludes a block-related pair (either direction); in-game opponent card gains a ✖️ **block** control (mirroring 🤝, red "Block?" confirm, mutual-hide, struck name + hidden chat composer when blocked); optimistic apply + `user_blocked`/`user_unblocked` event confirm + rollback; admin user card gains **blocks / blocked-by / friends** cross-linked lists. Blocking a disguised-robot opponent is recorded per-game in a separate **`robot_blocks`** table (migration `00011`), keyed on game+seat with the seen name — never the shared robot account — so the matchmaker keeps giving robots; it shows in the blocked list and re-marks the in-game card | owner ad-hoc | **done** |
 | → | Stage 18 — prod contour deploy | — | see [`PLAN.md`](PLAN.md) |
 
 ## Key findings (these reshaped the raw list — read before starting a phase)

backend/internal/inttest/block_test.go

@@ -10,7 +10,9 @@ import (
 
 	"github.com/google/uuid"
 
+	"scrabble/backend/internal/account"
 	"scrabble/backend/internal/engine"
+	"scrabble/backend/internal/game"
 	"scrabble/backend/internal/notify"
 	"scrabble/backend/internal/social"
 )
@@ -249,6 +251,56 @@ func TestAdminSocialLists(t *testing.T) {
 	}
 }
 
+// TestRobotBlockIsPerGameAndMatchmakerImmune checks that blocking a disguised-robot opponent
+// is recorded per-game in robot_blocks — never in the blocks table or against the shared robot
+// account — so the matchmaker keeps the robot free, and that unblocking by the row id removes it.
+func TestRobotBlockIsPerGameAndMatchmakerImmune(t *testing.T) {
+	ctx := context.Background()
+	svc := newSocialService()
+	accs := account.NewStore(testDB)
+	human := provisionAccount(t)
+	robot, err := accs.ProvisionRobot(ctx, "robot-block-"+uuid.NewString(), "Robbie")
+	if err != nil {
+		t.Fatalf("provision robot: %v", err)
+	}
+	g, err := newGameService().Create(ctx, game.CreateParams{
+		Variant: engine.VariantEnglish, Seats: []uuid.UUID{human, robot.ID},
+		TurnTimeout: 24 * time.Hour, Seed: openingSeed(t),
+	})
+	if err != nil {
+		t.Fatalf("create game: %v", err)
+	}
+
+	if err := svc.BlockInGame(ctx, human, robot.ID, g.ID); err != nil {
+		t.Fatalf("block robot: %v", err)
+	}
+	rbs, err := svc.ListRobotBlocks(ctx, human)
+	if err != nil {
+		t.Fatalf("list robot blocks: %v", err)
+	}
+	if len(rbs) != 1 || rbs[0].GameID != g.ID {
+		t.Fatalf("robot blocks = %v, want one for game %s", rbs, g.ID)
+	}
+	if bl, _ := svc.ListBlocks(ctx, human); len(bl) != 0 {
+		t.Errorf("blocks table must stay empty for a robot block, got %v", bl)
+	}
+	if yes, _ := svc.IsBlocked(ctx, human, robot.ID); yes {
+		t.Error("the shared robot account must never be blocked")
+	}
+	// Matchmaking immunity: the robot is never in the caller's exclusion set, so the matchmaker
+	// keeps giving robots and the player can never be starved by blocking them.
+	if with, _ := svc.BlockedWith(ctx, human); contains(with, robot.ID) {
+		t.Error("a robot block must not put the robot in BlockedWith")
+	}
+	// Unblock by the robot_blocks row id removes it.
+	if err := svc.Unblock(ctx, human, rbs[0].ID); err != nil {
+		t.Fatalf("unblock robot: %v", err)
+	}
+	if rbs, _ := svc.ListRobotBlocks(ctx, human); len(rbs) != 0 {
+		t.Errorf("robot block not removed by unblock: %v", rbs)
+	}
+}
+
 // blockedWith reads the both-direction block set for id.
 func blockedWith(t *testing.T, soc *social.Service, id uuid.UUID) []uuid.UUID {
 	t.Helper()

backend/internal/postgres/migrations/00011_robot_blocks.sql

@@ -0,0 +1,27 @@
+-- +goose Up
+-- Per-game blocks of a disguised-robot opponent. A disguised robot is a shared pool
+-- account reused across games under different per-game names, so it must never go into
+-- `blocks` (that would make the same robot look blocked in the blocker's other games under
+-- other names, leaking that it is a bot, and show its pool name instead of the one seen).
+-- Each such block is recorded here against the specific game + seat, snapshotting the name
+-- the player saw, so the blocked list shows it as a distinct personality and the in-game
+-- card re-marks that one seat. The real robot account is never blocked, so the matchmaker
+-- leaves robots free. Unblocking deletes the row.
+SET search_path = backend, pg_catalog;
+
+CREATE TABLE robot_blocks (
+    id           uuid        PRIMARY KEY,
+    blocker_id   uuid        NOT NULL REFERENCES accounts (account_id) ON DELETE CASCADE,
+    game_id      uuid        NOT NULL REFERENCES games (game_id) ON DELETE CASCADE,
+    seat         smallint    NOT NULL,
+    robot_id     uuid        NOT NULL REFERENCES accounts (account_id) ON DELETE CASCADE,
+    display_name text        NOT NULL,
+    created_at   timestamptz NOT NULL DEFAULT now(),
+    UNIQUE (blocker_id, game_id, seat)
+);
+
+CREATE INDEX robot_blocks_blocker_idx ON robot_blocks (blocker_id);
+
+-- +goose Down
+SET search_path = backend, pg_catalog;
+DROP TABLE robot_blocks;

backend/internal/server/handlers_blocks.go

@@ -2,6 +2,7 @@ package server
 
 import (
 	"net/http"
+	"strings"
 
 	"github.com/gin-gonic/gin"
 	"github.com/google/uuid"
@@ -13,9 +14,21 @@ import (
 // not delete — any friendship (an unblock restores it). They reuse the friend handlers'
 // targetIDRequest and account-ref resolution.
 
-// blockListDTO is the accounts the caller has blocked.
+// blockListDTO is the accounts the caller has blocked, plus the per-game disguised-robot
+// blocks (not real accounts), which the blocked list shows as distinct personalities.
 type blockListDTO struct {
 	Blocked []accountRefDTO `json:"blocked"`
+	Robots  []robotBlockDTO `json:"robots"`
+}
+
+// robotBlockDTO is one per-game disguised-robot block: the row id (used to unblock it), the
+// game name the player saw, and the game + seat it was blocked in (so the in-game card can
+// re-mark that seat).
+type robotBlockDTO struct {
+	ID          string `json:"id"`
+	DisplayName string `json:"display_name"`
+	GameID      string `json:"game_id"`
+	Seat        int    `json:"seat"`
 }
 
 // handleBlock blocks the body-supplied account.
@@ -35,7 +48,18 @@ func (s *Server) handleBlock(c *gin.Context) {
 		abortBadRequest(c, "invalid account id")
 		return
 	}
-	if err := s.social.Block(c.Request.Context(), uid, target); err != nil {
+	// An in-game block carries the game id, so a disguised-robot opponent is recorded as a
+	// per-game block (BlockInGame); a settings-screen block (no game) blocks a human directly.
+	var err error
+	if strings.TrimSpace(req.GameID) == "" {
+		err = s.social.Block(c.Request.Context(), uid, target)
+	} else if gameID, ok := parseUUIDField(req.GameID); !ok {
+		abortBadRequest(c, "invalid game id")
+		return
+	} else {
+		err = s.social.BlockInGame(c.Request.Context(), uid, target, gameID)
+	}
+	if err != nil {
 		s.abortErr(c, err)
 		return
 	}
@@ -68,10 +92,20 @@ func (s *Server) handleListBlocks(c *gin.Context) {
 		abortBadRequest(c, "missing identity")
 		return
 	}
-	ids, err := s.social.ListBlocks(c.Request.Context(), uid)
+	ctx := c.Request.Context()
+	ids, err := s.social.ListBlocks(ctx, uid)
 	if err != nil {
 		s.abortErr(c, err)
 		return
 	}
-	c.JSON(http.StatusOK, blockListDTO{Blocked: s.accountRefs(c.Request.Context(), ids)})
+	robots, err := s.social.ListRobotBlocks(ctx, uid)
+	if err != nil {
+		s.abortErr(c, err)
+		return
+	}
+	dto := blockListDTO{Blocked: s.accountRefs(ctx, ids)}
+	for _, r := range robots {
+		dto.Robots = append(dto.Robots, robotBlockDTO{ID: r.ID.String(), DisplayName: r.DisplayName, GameID: r.GameID.String(), Seat: r.Seat})
+	}
+	c.JSON(http.StatusOK, dto)
 }

backend/internal/server/handlers_friends.go

@@ -48,9 +48,12 @@ type redeemResultDTO struct {
 	Friend accountRefDTO `json:"friend"`
 }
 
-// targetIDRequest carries a single counterpart account id.
+// targetIDRequest carries a single counterpart account id. GameID is set only by an
+// in-game block (so a disguised-robot opponent can be recorded as a per-game block); the
+// other target paths leave it empty.
 type targetIDRequest struct {
 	AccountID string `json:"account_id"`
+	GameID    string `json:"game_id"`
 }
 
 // friendRespondRequest accepts or declines a pending request from a requester.

backend/internal/social/blocks.go

@@ -35,15 +35,23 @@ func (svc *Service) Block(ctx context.Context, blockerID, blockedID uuid.UUID) e
 	return nil
 }
 
-// Unblock removes blockerID's block on blockedID and confirms it to the (former)
+// Unblock removes blockerID's block on the given target and confirms it to the (former)
-// blocker with a user_unblocked event so their open game screens restore the controls
+// blocker with a user_unblocked event so their open game screens restore the controls and
-// and un-strike the name in place. Any friendship the block had been overriding becomes
+// un-strike the name in place. The target is either a blocked human's account id (the
-// effective again. It is idempotent.
+// blocks table) or a robot_blocks row id (a per-game disguised-robot block) — the robot
-func (svc *Service) Unblock(ctx context.Context, blockerID, blockedID uuid.UUID) error {
+// block is tried first, falling back to the human block. Any friendship the block had been
-	if err := svc.store.deleteBlock(ctx, blockerID, blockedID); err != nil {
+// overriding becomes effective again. It is idempotent.
+func (svc *Service) Unblock(ctx context.Context, blockerID, target uuid.UUID) error {
+	removed, err := svc.store.deleteRobotBlock(ctx, blockerID, target)
+	if err != nil {
 		return err
 	}
-	svc.pub.Publish(notify.NotificationAccount(blockerID, notify.NotifyUserUnblocked, svc.accountRef(ctx, blockedID)))
+	if !removed {
+		if err := svc.store.deleteBlock(ctx, blockerID, target); err != nil {
+			return err
+		}
+	}
+	svc.pub.Publish(notify.NotificationAccount(blockerID, notify.NotifyUserUnblocked, svc.accountRef(ctx, target)))
 	return nil
 }
 

backend/internal/social/robotblocks.go

@@ -0,0 +1,115 @@
+package social
+
+import (
+	"context"
+	"fmt"
+	"slices"
+
+	"github.com/google/uuid"
+
+	"scrabble/backend/internal/notify"
+)
+
+// RobotBlock is one per-game block of a disguised-robot opponent: the row id (used to
+// unblock it), the game name the player saw, and the game + seat it was blocked in.
+type RobotBlock struct {
+	ID          uuid.UUID
+	DisplayName string
+	GameID      uuid.UUID
+	Seat        int
+}
+
+// BlockInGame blocks blockedID for blockerID from within gameID. A human is blocked
+// normally (the blocks table, via Block). A disguised-robot opponent is instead recorded
+// per-game in robot_blocks — never the shared robot account — so the matchmaker keeps
+// robots free and the same robot stays unblocked in the blocker's other games (under its
+// other names); the row snapshots the seat and the name the player saw so the blocked list
+// and the in-game card can show it. It is the entry point for the in-game block control;
+// the settings-screen block (no game) goes through Block directly.
+func (svc *Service) BlockInGame(ctx context.Context, blockerID, blockedID, gameID uuid.UUID) error {
+	if blockerID == blockedID {
+		return ErrSelfRelation
+	}
+	isRobot, err := svc.accounts.IsRobot(ctx, blockedID)
+	if err != nil {
+		return err
+	}
+	if !isRobot {
+		return svc.Block(ctx, blockerID, blockedID)
+	}
+	if gameID == uuid.Nil {
+		return ErrNotParticipant
+	}
+	seats, _, _, err := svc.games.Participants(ctx, gameID)
+	if err != nil {
+		return err
+	}
+	seat := slices.Index(seats, blockedID)
+	if seat < 0 {
+		return ErrNotParticipant
+	}
+	name, _ := svc.games.SeatName(ctx, gameID, blockedID)
+	if err := svc.store.insertRobotBlock(ctx, blockerID, gameID, seat, blockedID, name); err != nil {
+		return err
+	}
+	svc.pub.Publish(notify.NotificationAccount(blockerID, notify.NotifyUserBlocked, svc.accountRef(ctx, blockedID)))
+	return nil
+}
+
+// ListRobotBlocks returns blockerID's per-game disguised-robot blocks, newest first.
+func (svc *Service) ListRobotBlocks(ctx context.Context, blockerID uuid.UUID) ([]RobotBlock, error) {
+	return svc.store.listRobotBlocks(ctx, blockerID)
+}
+
+// insertRobotBlock records a per-game robot block; a duplicate (same blocker, game, seat)
+// is ignored.
+func (s *Store) insertRobotBlock(ctx context.Context, blocker, gameID uuid.UUID, seat int, robotID uuid.UUID, name string) error {
+	id, err := uuid.NewV7()
+	if err != nil {
+		return fmt.Errorf("social: new robot block id: %w", err)
+	}
+	const q = `INSERT INTO backend.robot_blocks (id, blocker_id, game_id, seat, robot_id, display_name)
+VALUES ($1, $2, $3, $4, $5, $6)
+ON CONFLICT (blocker_id, game_id, seat) DO NOTHING`
+	if _, err := s.db.ExecContext(ctx, q, id, blocker, gameID, int16(seat), robotID, name); err != nil {
+		return fmt.Errorf("social: insert robot block: %w", err)
+	}
+	return nil
+}
+
+// deleteRobotBlock removes blocker's robot block by its row id, reporting whether a row
+// matched (so the caller can fall back to a human block).
+func (s *Store) deleteRobotBlock(ctx context.Context, blocker, id uuid.UUID) (bool, error) {
+	const q = `DELETE FROM backend.robot_blocks WHERE id = $2 AND blocker_id = $1`
+	res, err := s.db.ExecContext(ctx, q, blocker, id)
+	if err != nil {
+		return false, fmt.Errorf("social: delete robot block: %w", err)
+	}
+	n, err := res.RowsAffected()
+	if err != nil {
+		return false, fmt.Errorf("social: delete robot block rows: %w", err)
+	}
+	return n > 0, nil
+}
+
+// listRobotBlocks returns blocker's robot blocks, newest first.
+func (s *Store) listRobotBlocks(ctx context.Context, blocker uuid.UUID) ([]RobotBlock, error) {
+	const q = `SELECT id, display_name, game_id, seat FROM backend.robot_blocks
+WHERE blocker_id = $1 ORDER BY created_at DESC`
+	rows, err := s.db.QueryContext(ctx, q, blocker)
+	if err != nil {
+		return nil, fmt.Errorf("social: list robot blocks: %w", err)
+	}
+	defer rows.Close()
+	var out []RobotBlock
+	for rows.Next() {
+		var rb RobotBlock
+		var seat int16
+		if err := rows.Scan(&rb.ID, &rb.DisplayName, &rb.GameID, &seat); err != nil {
+			return nil, fmt.Errorf("social: scan robot block: %w", err)
+		}
+		rb.Seat = int(seat)
+		out = append(out, rb)
+	}
+	return out, rows.Err()
+}

docs/ARCHITECTURE.md

@@ -520,7 +520,12 @@ in either direction (the enqueue excludes the caller's `BlockedWith` set);
   **overrides but does not delete** a friendship (an unblock cleanly restores it), so a pair may
   be friends **and** blocked at once; the admin user card shows the full truth (blocks,
   blocked-by, friends) regardless of this suppression. Block/unblock emit a `user_blocked` /
-  `user_unblocked` notification to the blocker only (§10).
+  `user_unblocked` notification to the blocker only (§10). Blocking an auto-match opponent who
+  is secretly a pooled robot is recorded instead in a separate **`robot_blocks`** table, keyed on
+  the blocker + game + seat with the seen name snapshotted (`BlockInGame`): the shared robot
+  account is never put in `blocks` (so the matchmaker keeps it free and it is not blocked under
+  its other per-game names), while the blocked list and the in-game card still show it by joining
+  that table; an unblock deletes the row.
 - **Friend games**: formed by **invitation → accept** (an `game_invitations`
   record with one row per invitee). The 2–4 player game starts once **every**
   invitee accepts; any decline cancels the invitation, and a pending invitation

docs/FUNCTIONAL.md

@@ -198,7 +198,12 @@ read at once), and a friend request or invitation they send you is kept but neve
 block **overrides but does not delete** an existing friendship (so you may block a friend, and
 they keep seeing you as one); active games are never interrupted — you can finish them, with
 the blocked opponent's chat composer hidden (only the log remains). Blocking from a game card
-mirrors the block in **Settings → Friends**; **unblock** and **unfriend** live there only. Per-game chat is for quick reactions: messages are short
+mirrors the block in **Settings → Friends**; **unblock** and **unfriend** live there only.
+Blocking an **auto-match opponent who is secretly a robot** behaves the same in that game
+(struck name, hidden composer) and lists the blocked opponent under the name you saw, but is
+recorded only against that game — the disguise holds, the shared robot is never globally
+blocked, and the matchmaker keeps pairing you with robots (so you can never block yourself out
+of opponents). Per-game chat is for quick reactions: messages are short
 (up to 60 characters) and may not contain links, email addresses or phone numbers,
 even disguised. You may send **one message per turn, on your own turn**; once it is sent
 the field gives way to a short caption until your next turn. Nudge the player whose turn

docs/FUNCTIONAL_ru.md

@@ -203,7 +203,12 @@ nudge) приходят от бота **этой партии** — по язы
 продолжает видеть вас в друзьях); активные игры не прерываются — их можно доигрывать, при этом у
 заблокированного соперника «подвал» чата скрыт (остаётся только лог). Блокировка с карточки в
 партии повторяет блокировку в **Настройках → Друзья**; **разблокировка** и **удаление из друзей**
-есть только там. Чат
+есть только там.
+Блокировка **авто-матч соперника, который втайне робот**, в этой партии ведёт себя так же
+(зачёркнутое имя, скрытый «подвал») и в списке заблокированных показывается под тем именем,
+которое ты видел, но записывается только для этой партии — маскировка сохраняется, общий
+аккаунт робота глобально не блокируется, и матчмейкер продолжает давать роботов (так что
+заблокировать себя без соперников нельзя). Чат
 партии — для быстрых реакций: сообщения короткие (до 60 символов) и не должны
 содержать ссылок, email и телефонов, даже завуалированных. В свой ход можно отправить
 **одно сообщение за ход**; после отправки поле сменяется короткой подписью до следующего

gateway/internal/backendclient/api_social.go

@@ -42,9 +42,20 @@ type RedeemResultResp struct {
 	Friend AccountRefResp `json:"friend"`
 }
 
-// BlockListResp is the accounts the caller has blocked.
+// BlockListResp is the accounts the caller has blocked, plus the per-game disguised-robot
+// blocks (not real accounts).
 type BlockListResp struct {
 	Blocked []AccountRefResp `json:"blocked"`
+	Robots  []RobotBlockResp `json:"robots"`
+}
+
+// RobotBlockResp is one per-game disguised-robot block: the row id (to unblock it), the game
+// name the player saw, and the game + seat it was blocked in.
+type RobotBlockResp struct {
+	ID          string `json:"id"`
+	DisplayName string `json:"display_name"`
+	GameID      string `json:"game_id"`
+	Seat        int    `json:"seat"`
 }
 
 // StatsResp is a durable account's lifetime statistics. BestMoves breaks the best move
@@ -188,10 +199,11 @@ func (c *Client) RedeemFriendCode(ctx context.Context, userID, code string) (Red
 
 // --- blocks ---
 
-// Block blocks an account.
+// Block blocks an account. A non-empty gameID marks an in-game block, so a disguised-robot
-func (c *Client) Block(ctx context.Context, userID, targetID string) error {
+// opponent is recorded as a per-game block; it is empty for a settings-screen block.
+func (c *Client) Block(ctx context.Context, userID, targetID, gameID string) error {
 	return c.do(ctx, http.MethodPost, "/api/v1/user/blocks", userID, "",
-		map[string]string{"account_id": targetID}, nil)
+		map[string]string{"account_id": targetID, "game_id": gameID}, nil)
 }
 
 // Unblock removes a block.

gateway/internal/transcode/encode_social.go

@@ -60,12 +60,35 @@ func encodeOutgoingList(r backendclient.OutgoingListResp) []byte {
 	return b.FinishedBytes()
 }
 
+// buildRobotBlockVector builds the BlockList robots vector (per-game disguised-robot blocks).
+func buildRobotBlockVector(b *flatbuffers.Builder, robots []backendclient.RobotBlockResp) flatbuffers.UOffsetT {
+	offs := make([]flatbuffers.UOffsetT, len(robots))
+	for i, r := range robots {
+		id := b.CreateString(r.ID)
+		name := b.CreateString(r.DisplayName)
+		gid := b.CreateString(r.GameID)
+		fb.RobotBlockRefStart(b)
+		fb.RobotBlockRefAddId(b, id)
+		fb.RobotBlockRefAddDisplayName(b, name)
+		fb.RobotBlockRefAddGameId(b, gid)
+		fb.RobotBlockRefAddSeat(b, int32(r.Seat))
+		offs[i] = fb.RobotBlockRefEnd(b)
+	}
+	fb.BlockListStartRobotsVector(b, len(offs))
+	for i := len(offs) - 1; i >= 0; i-- {
+		b.PrependUOffsetT(offs[i])
+	}
+	return b.EndVector(len(offs))
+}
+
 // encodeBlockList builds a BlockList payload.
 func encodeBlockList(r backendclient.BlockListResp) []byte {
 	b := flatbuffers.NewBuilder(256)
 	v := buildAccountRefVector(b, r.Blocked, fb.BlockListStartBlockedVector)
+	rv := buildRobotBlockVector(b, r.Robots)
 	fb.BlockListStart(b)
 	fb.BlockListAddBlocked(b, v)
+	fb.BlockListAddRobots(b, rv)
 	b.Finish(fb.BlockListEnd(b))
 	return b.FinishedBytes()
 }

gateway/internal/transcode/transcode_social.go

@@ -166,7 +166,9 @@ func blocksListHandler(backend *backendclient.Client) Handler {
 func blockAddHandler(backend *backendclient.Client) Handler {
 	return func(ctx context.Context, req Request) ([]byte, error) {
 		in := fb.GetRootAsTargetRequest(req.Payload, 0)
-		if err := backend.Block(ctx, req.UserID, string(in.AccountId())); err != nil {
+		// game_id is set only by an in-game block, so a disguised-robot opponent is recorded
+		// per-game; it is empty for a settings-screen block.
+		if err := backend.Block(ctx, req.UserID, string(in.AccountId()), string(in.GameId())); err != nil {
 			return nil, err
 		}
 		return encodeAck(true), nil

pkg/fbs/scrabble.fbs

@@ -504,9 +504,12 @@ table StatsView {
 }
 
 // TargetRequest names a single counterpart account (friend request/cancel/unfriend,
-// block/unblock).
+// block/unblock). game_id is set only by an in-game block of a disguised-robot opponent,
+// so the backend can record the per-game robot block (the seat name the player saw)
+// against that game; every other path leaves it empty (FlatBuffers-optional).
 table TargetRequest {
   account_id:string;
+  game_id:string;
 }
 
 // FriendRespondRequest accepts or declines a pending request from a requester.
@@ -548,9 +551,22 @@ table RedeemResult {
   friend:AccountRef;
 }
 
-// BlockList is the accounts the caller has blocked.
+// RobotBlockRef is one blocked disguised-robot opponent: a per-game record (not a real
+// account) carrying the game name the player saw and the game/seat it was blocked in, so
+// the blocked list shows it as a distinct personality and the in-game card can re-mark
+// that seat. Its id is the robot_blocks row, used to unblock it.
+table RobotBlockRef {
+  id:string;
+  display_name:string;
+  game_id:string;
+  seat:int;
+}
+
+// BlockList is the accounts the caller has blocked, plus the per-game disguised-robot
+// blocks (robots) which are not real accounts.
 table BlockList {
   blocked:[AccountRef];
+  robots:[RobotBlockRef];
 }
 
 // InvitationInvitee is one invitee's seat and response, name resolved.

pkg/fbs/scrabblefb/BlockList.go

@@ -61,8 +61,28 @@ func (rcv *BlockList) BlockedLength() int {
 	return 0
 }
 
+func (rcv *BlockList) Robots(obj *RobotBlockRef, j int) bool {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(6))
+	if o != 0 {
+		x := rcv._tab.Vector(o)
+		x += flatbuffers.UOffsetT(j) * 4
+		x = rcv._tab.Indirect(x)
+		obj.Init(rcv._tab.Bytes, x)
+		return true
+	}
+	return false
+}
+
+func (rcv *BlockList) RobotsLength() int {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(6))
+	if o != 0 {
+		return rcv._tab.VectorLen(o)
+	}
+	return 0
+}
+
 func BlockListStart(builder *flatbuffers.Builder) {
-	builder.StartObject(1)
+	builder.StartObject(2)
 }
 func BlockListAddBlocked(builder *flatbuffers.Builder, blocked flatbuffers.UOffsetT) {
 	builder.PrependUOffsetTSlot(0, flatbuffers.UOffsetT(blocked), 0)
@@ -70,6 +90,12 @@ func BlockListAddBlocked(builder *flatbuffers.Builder, blocked flatbuffers.UOffs
 func BlockListStartBlockedVector(builder *flatbuffers.Builder, numElems int) flatbuffers.UOffsetT {
 	return builder.StartVector(4, numElems, 4)
 }
+func BlockListAddRobots(builder *flatbuffers.Builder, robots flatbuffers.UOffsetT) {
+	builder.PrependUOffsetTSlot(1, flatbuffers.UOffsetT(robots), 0)
+}
+func BlockListStartRobotsVector(builder *flatbuffers.Builder, numElems int) flatbuffers.UOffsetT {
+	return builder.StartVector(4, numElems, 4)
+}
 func BlockListEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
 	return builder.EndObject()
 }

pkg/fbs/scrabblefb/RobotBlockRef.go

@@ -0,0 +1,97 @@
+// Code generated by the FlatBuffers compiler. DO NOT EDIT.
+
+package scrabblefb
+
+import (
+	flatbuffers "github.com/google/flatbuffers/go"
+)
+
+type RobotBlockRef struct {
+	_tab flatbuffers.Table
+}
+
+func GetRootAsRobotBlockRef(buf []byte, offset flatbuffers.UOffsetT) *RobotBlockRef {
+	n := flatbuffers.GetUOffsetT(buf[offset:])
+	x := &RobotBlockRef{}
+	x.Init(buf, n+offset)
+	return x
+}
+
+func FinishRobotBlockRefBuffer(builder *flatbuffers.Builder, offset flatbuffers.UOffsetT) {
+	builder.Finish(offset)
+}
+
+func GetSizePrefixedRootAsRobotBlockRef(buf []byte, offset flatbuffers.UOffsetT) *RobotBlockRef {
+	n := flatbuffers.GetUOffsetT(buf[offset+flatbuffers.SizeUint32:])
+	x := &RobotBlockRef{}
+	x.Init(buf, n+offset+flatbuffers.SizeUint32)
+	return x
+}
+
+func FinishSizePrefixedRobotBlockRefBuffer(builder *flatbuffers.Builder, offset flatbuffers.UOffsetT) {
+	builder.FinishSizePrefixed(offset)
+}
+
+func (rcv *RobotBlockRef) Init(buf []byte, i flatbuffers.UOffsetT) {
+	rcv._tab.Bytes = buf
+	rcv._tab.Pos = i
+}
+
+func (rcv *RobotBlockRef) Table() flatbuffers.Table {
+	return rcv._tab
+}
+
+func (rcv *RobotBlockRef) Id() []byte {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(4))
+	if o != 0 {
+		return rcv._tab.ByteVector(o + rcv._tab.Pos)
+	}
+	return nil
+}
+
+func (rcv *RobotBlockRef) DisplayName() []byte {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(6))
+	if o != 0 {
+		return rcv._tab.ByteVector(o + rcv._tab.Pos)
+	}
+	return nil
+}
+
+func (rcv *RobotBlockRef) GameId() []byte {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(8))
+	if o != 0 {
+		return rcv._tab.ByteVector(o + rcv._tab.Pos)
+	}
+	return nil
+}
+
+func (rcv *RobotBlockRef) Seat() int32 {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(10))
+	if o != 0 {
+		return rcv._tab.GetInt32(o + rcv._tab.Pos)
+	}
+	return 0
+}
+
+func (rcv *RobotBlockRef) MutateSeat(n int32) bool {
+	return rcv._tab.MutateInt32Slot(10, n)
+}
+
+func RobotBlockRefStart(builder *flatbuffers.Builder) {
+	builder.StartObject(4)
+}
+func RobotBlockRefAddId(builder *flatbuffers.Builder, id flatbuffers.UOffsetT) {
+	builder.PrependUOffsetTSlot(0, flatbuffers.UOffsetT(id), 0)
+}
+func RobotBlockRefAddDisplayName(builder *flatbuffers.Builder, displayName flatbuffers.UOffsetT) {
+	builder.PrependUOffsetTSlot(1, flatbuffers.UOffsetT(displayName), 0)
+}
+func RobotBlockRefAddGameId(builder *flatbuffers.Builder, gameId flatbuffers.UOffsetT) {
+	builder.PrependUOffsetTSlot(2, flatbuffers.UOffsetT(gameId), 0)
+}
+func RobotBlockRefAddSeat(builder *flatbuffers.Builder, seat int32) {
+	builder.PrependInt32Slot(3, seat, 0)
+}
+func RobotBlockRefEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
+	return builder.EndObject()
+}

pkg/fbs/scrabblefb/TargetRequest.go

@@ -49,12 +49,23 @@ func (rcv *TargetRequest) AccountId() []byte {
 	return nil
 }
 
+func (rcv *TargetRequest) GameId() []byte {
+	o := flatbuffers.UOffsetT(rcv._tab.Offset(6))
+	if o != 0 {
+		return rcv._tab.ByteVector(o + rcv._tab.Pos)
+	}
+	return nil
+}
+
 func TargetRequestStart(builder *flatbuffers.Builder) {
-	builder.StartObject(1)
+	builder.StartObject(2)
 }
 func TargetRequestAddAccountId(builder *flatbuffers.Builder, accountId flatbuffers.UOffsetT) {
 	builder.PrependUOffsetTSlot(0, flatbuffers.UOffsetT(accountId), 0)
 }
+func TargetRequestAddGameId(builder *flatbuffers.Builder, gameId flatbuffers.UOffsetT) {
+	builder.PrependUOffsetTSlot(1, flatbuffers.UOffsetT(gameId), 0)
+}
 func TargetRequestEnd(builder *flatbuffers.Builder) flatbuffers.UOffsetT {
 	return builder.EndObject()
 }

ui/src/game/ChatScreen.svelte

@@ -17,8 +17,10 @@
   let busy = $state(false);
   let tick = $state(0);
   // The opponents the viewer has blocked: when every opponent is blocked the composer is hidden
-  // (only the chat log remains), matching the backend guard that rejects messaging a blocked peer.
+  // (only the chat log remains). blockedIds are blocked humans (by account); blockedRobotSeats are
+  // the seats of blocked disguised robots in this game (a robot block is per game+seat).
   let blockedIds = $state(new Set<string>());
+  let blockedRobotSeats = $state(new Set<number>());
 
   const myId = $derived(app.session?.userId ?? '');
   const isMyTurn = $derived(
@@ -40,7 +42,10 @@
     const v = view;
     if (!v) return false;
     const opponents = v.game.seats.filter((s) => s.seat !== v.seat && !!s.accountId);
-    return opponents.length > 0 && opponents.every((s) => blockedIds.has(s.accountId));
+    return (
+      opponents.length > 0 &&
+      opponents.every((s) => blockedIds.has(s.accountId) || blockedRobotSeats.has(s.seat))
+    );
   });
   const nudgeCooldownSecs = 3600;
   // The nudge is one-per-hour-per-game and clears once the player chats (engagement); the
@@ -80,7 +85,8 @@
     if (app.profile?.isGuest) return;
     try {
       const bl = await gateway.blocksList();
-      blockedIds = new Set(bl.map((b) => b.accountId));
+      blockedIds = new Set(bl.blocked.map((b) => b.accountId));
+      blockedRobotSeats = new Set(bl.robots.filter((r) => r.gameId === id).map((r) => r.seat));
     } catch {
       /* best-effort */
     }

ui/src/game/Game.svelte

@@ -892,8 +892,11 @@
   let requested = $state(new Set<string>());
   // `blocked` are the opponents the viewer has blocked: their 🤝 and ✖️ controls disappear and
   // their name is struck. Derived from the server so it is correct across reloads and live-updates
-  // on a user_blocked / user_unblocked event.
+  // on a user_blocked / user_unblocked event. `blockedRobotSeats` are the seat indices of blocked
+  // disguised-robot opponents in THIS game (a robot block is recorded per game+seat, not by
+  // account, so it never touches the shared robot account or other games).
   let blocked = $state(new Set<string>());
+  let blockedRobotSeats = $state(new Set<number>());
   // Per-seat "confirming" flags for the 🤝 → ✅ and ✖️ → ✅ tap-to-confirm (TapConfirm writes them);
   // while set, that seat's card shows "Add friend?" / "Block?" in place of the score, and the
   // opposite control is hidden so the two never overlap. Reset when history closes.
@@ -913,17 +916,25 @@
     }
   }
 
-  // loadBlocked refreshes the blocked set for a non-guest. Best-effort.
+  // loadBlocked refreshes the blocked sets for a non-guest: blocked humans by account, plus the
+  // seats of any blocked disguised robots in this game. Best-effort.
   async function loadBlocked() {
     if (app.profile?.isGuest) return;
     try {
       const bl = await gateway.blocksList();
-      blocked = new Set(bl.map((b) => b.accountId));
+      blocked = new Set(bl.blocked.map((b) => b.accountId));
+      blockedRobotSeats = new Set(bl.robots.filter((r) => r.gameId === id).map((r) => r.seat));
     } catch {
       /* best-effort */
     }
   }
 
+  // seatBlocked reports whether the viewer has blocked this seat — a human (by account) or a
+  // disguised robot (by this game's seat). It drives the struck name and hidden controls.
+  function seatBlocked(s: { accountId: string; seat: number }): boolean {
+    return blocked.has(s.accountId) || blockedRobotSeats.has(s.seat);
+  }
+
   // addFriend and blockUser apply the new relationship optimistically (so the controls and score
   // caption update the instant the confirm fires) and roll back to the prior state if the command
   // fails to reach the server. The confirming user_blocked / user_added event then just reconciles
@@ -940,13 +951,16 @@
     }
   }
 
-  async function blockUser(accountId: string) {
+  async function blockUser(s: { accountId: string; seat: number }) {
-    const had = blocked.has(accountId);
+    // Optimistically mark this seat blocked (covers the struck name + hidden controls for both a
-    blocked = new Set([...blocked, accountId]);
+    // human and a disguised robot until the server confirms). The block carries the game id so a
+    // robot opponent is recorded as a per-game block; the user_blocked event then reconciles.
+    const hadSeat = blockedRobotSeats.has(s.seat);
+    blockedRobotSeats = new Set([...blockedRobotSeats, s.seat]);
     try {
-      await gateway.block(accountId);
+      await gateway.block(s.accountId, id);
     } catch (e) {
-      if (!had) blocked = new Set([...blocked].filter((id) => id !== accountId));
+      if (!hadSeat) blockedRobotSeats = new Set([...blockedRobotSeats].filter((x) => x !== s.seat));
       handleError(e);
     }
   }
@@ -975,26 +989,24 @@
   // canAddFriend reports whether a seat shows the 🤝: a non-guest viewing a seated opponent
   // (not the still-empty seat of an open game) who is not yet a friend (an already-requested
   // opponent still shows it, but disabled).
-  function canAddFriend(accountId: string): boolean {
+  function canAddFriend(s: { accountId: string; seat: number }): boolean {
     // Never offer add-friend against an AI opponent, an existing friend, or a blocked player.
     if (view?.game.vsAi) return false;
     return (
-      !!accountId &&
+      !!s.accountId &&
       !app.profile?.isGuest &&
-      accountId !== app.session?.userId &&
+      s.accountId !== app.session?.userId &&
-      !friends.has(accountId) &&
+      !friends.has(s.accountId) &&
-      !blocked.has(accountId)
+      !seatBlocked(s)
     );
   }
 
   // canBlock reports whether a seat shows the ✖️ block control: like canAddFriend, but a friend
   // may still be blocked (the block overrides the friendship), so it omits the friend exclusion.
   // An already-blocked opponent hides it (both controls go, and the name is struck).
-  function canBlock(accountId: string): boolean {
+  function canBlock(s: { accountId: string; seat: number }): boolean {
     if (view?.game.vsAi) return false;
-    return (
+    return !!s.accountId && !app.profile?.isGuest && s.accountId !== app.session?.userId && !seatBlocked(s);
-      !!accountId && !app.profile?.isGuest && accountId !== app.session?.userId && !blocked.has(accountId)
-    );
   }
 </script>
 
@@ -1044,22 +1056,22 @@
       {#if app.chatUnread[id]}<span class="unread-dot sbadge-dot"></span>{/if}
       {#each view.game.seats as s (s.seat)}
         <div class="seat" class:turn={view.game.toMove === s.seat && !gameOver} class:win={s.isWinner}>
-          <div class="nm" class:struck={blocked.has(s.accountId)}>{seatName(s)}</div>
+          <div class="nm" class:struck={seatBlocked(s)}>{seatName(s)}</div>
           <div class="sc" class:blockprompt={blockConfirm[s.seat]}>
             {#if blockConfirm[s.seat]}{t('game.blockShort')}{:else if addConfirm[s.seat]}{t('game.addFriendShort')}{:else}{s.score}{/if}
           </div>
-          {#if historyShown && canBlock(s.accountId) && !addConfirm[s.seat]}
+          {#if historyShown && canBlock(s) && !addConfirm[s.seat]}
             <span class="blockuser">
               <TapConfirm
                 label={t('friends.blockFromGame')}
                 onConfirming={(v) => (blockConfirm[s.seat] = v)}
-                onconfirm={() => blockUser(s.accountId)}
+                onconfirm={() => blockUser(s)}
               >
                 <span class="fico">✖️</span>
               </TapConfirm>
             </span>
           {/if}
-          {#if historyShown && canAddFriend(s.accountId) && !blockConfirm[s.seat]}
+          {#if historyShown && canAddFriend(s) && !blockConfirm[s.seat]}
             <span class="addfriend">
               <TapConfirm
                 label={t('friends.addFromGame')}

ui/src/gen/fbs/scrabblefb.ts

@@ -59,6 +59,7 @@ export { PlayTile } from './scrabblefb/play-tile.js';
 export { Profile } from './scrabblefb/profile.js';
 export { RedeemCodeRequest } from './scrabblefb/redeem-code-request.js';
 export { RedeemResult } from './scrabblefb/redeem-result.js';
+export { RobotBlockRef } from './scrabblefb/robot-block-ref.js';
 export { SeatView } from './scrabblefb/seat-view.js';
 export { Session } from './scrabblefb/session.js';
 export { StateRequest } from './scrabblefb/state-request.js';

ui/src/gen/fbs/scrabblefb/block-list.ts

@@ -3,6 +3,7 @@
 import * as flatbuffers from 'flatbuffers';
 
 import { AccountRef } from '../scrabblefb/account-ref.js';
+import { RobotBlockRef } from '../scrabblefb/robot-block-ref.js';
 
 
 export class BlockList {
@@ -33,8 +34,18 @@ blockedLength():number {
   return offset ? this.bb!.__vector_len(this.bb_pos + offset) : 0;
 }
 
+robots(index: number, obj?:RobotBlockRef):RobotBlockRef|null {
+  const offset = this.bb!.__offset(this.bb_pos, 6);
+  return offset ? (obj || new RobotBlockRef()).__init(this.bb!.__indirect(this.bb!.__vector(this.bb_pos + offset) + index * 4), this.bb!) : null;
+}
+
+robotsLength():number {
+  const offset = this.bb!.__offset(this.bb_pos, 6);
+  return offset ? this.bb!.__vector_len(this.bb_pos + offset) : 0;
+}
+
 static startBlockList(builder:flatbuffers.Builder) {
-  builder.startObject(1);
+  builder.startObject(2);
 }
 
 static addBlocked(builder:flatbuffers.Builder, blockedOffset:flatbuffers.Offset) {
@@ -53,14 +64,31 @@ static startBlockedVector(builder:flatbuffers.Builder, numElems:number) {
   builder.startVector(4, numElems, 4);
 }
 
+static addRobots(builder:flatbuffers.Builder, robotsOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(1, robotsOffset, 0);
+}
+
+static createRobotsVector(builder:flatbuffers.Builder, data:flatbuffers.Offset[]):flatbuffers.Offset {
+  builder.startVector(4, data.length, 4);
+  for (let i = data.length - 1; i >= 0; i--) {
+    builder.addOffset(data[i]!);
+  }
+  return builder.endVector();
+}
+
+static startRobotsVector(builder:flatbuffers.Builder, numElems:number) {
+  builder.startVector(4, numElems, 4);
+}
+
 static endBlockList(builder:flatbuffers.Builder):flatbuffers.Offset {
   const offset = builder.endObject();
   return offset;
 }
 
-static createBlockList(builder:flatbuffers.Builder, blockedOffset:flatbuffers.Offset):flatbuffers.Offset {
+static createBlockList(builder:flatbuffers.Builder, blockedOffset:flatbuffers.Offset, robotsOffset:flatbuffers.Offset):flatbuffers.Offset {
   BlockList.startBlockList(builder);
   BlockList.addBlocked(builder, blockedOffset);
+  BlockList.addRobots(builder, robotsOffset);
   return BlockList.endBlockList(builder);
 }
 }

ui/src/gen/fbs/scrabblefb/robot-block-ref.ts

@@ -0,0 +1,82 @@
+// automatically generated by the FlatBuffers compiler, do not modify
+
+import * as flatbuffers from 'flatbuffers';
+
+export class RobotBlockRef {
+  bb: flatbuffers.ByteBuffer|null = null;
+  bb_pos = 0;
+  __init(i:number, bb:flatbuffers.ByteBuffer):RobotBlockRef {
+  this.bb_pos = i;
+  this.bb = bb;
+  return this;
+}
+
+static getRootAsRobotBlockRef(bb:flatbuffers.ByteBuffer, obj?:RobotBlockRef):RobotBlockRef {
+  return (obj || new RobotBlockRef()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+static getSizePrefixedRootAsRobotBlockRef(bb:flatbuffers.ByteBuffer, obj?:RobotBlockRef):RobotBlockRef {
+  bb.setPosition(bb.position() + flatbuffers.SIZE_PREFIX_LENGTH);
+  return (obj || new RobotBlockRef()).__init(bb.readInt32(bb.position()) + bb.position(), bb);
+}
+
+id():string|null
+id(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
+id(optionalEncoding?:any):string|Uint8Array|null {
+  const offset = this.bb!.__offset(this.bb_pos, 4);
+  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
+}
+
+displayName():string|null
+displayName(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
+displayName(optionalEncoding?:any):string|Uint8Array|null {
+  const offset = this.bb!.__offset(this.bb_pos, 6);
+  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
+}
+
+gameId():string|null
+gameId(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
+gameId(optionalEncoding?:any):string|Uint8Array|null {
+  const offset = this.bb!.__offset(this.bb_pos, 8);
+  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
+}
+
+seat():number {
+  const offset = this.bb!.__offset(this.bb_pos, 10);
+  return offset ? this.bb!.readInt32(this.bb_pos + offset) : 0;
+}
+
+static startRobotBlockRef(builder:flatbuffers.Builder) {
+  builder.startObject(4);
+}
+
+static addId(builder:flatbuffers.Builder, idOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(0, idOffset, 0);
+}
+
+static addDisplayName(builder:flatbuffers.Builder, displayNameOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(1, displayNameOffset, 0);
+}
+
+static addGameId(builder:flatbuffers.Builder, gameIdOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(2, gameIdOffset, 0);
+}
+
+static addSeat(builder:flatbuffers.Builder, seat:number) {
+  builder.addFieldInt32(3, seat, 0);
+}
+
+static endRobotBlockRef(builder:flatbuffers.Builder):flatbuffers.Offset {
+  const offset = builder.endObject();
+  return offset;
+}
+
+static createRobotBlockRef(builder:flatbuffers.Builder, idOffset:flatbuffers.Offset, displayNameOffset:flatbuffers.Offset, gameIdOffset:flatbuffers.Offset, seat:number):flatbuffers.Offset {
+  RobotBlockRef.startRobotBlockRef(builder);
+  RobotBlockRef.addId(builder, idOffset);
+  RobotBlockRef.addDisplayName(builder, displayNameOffset);
+  RobotBlockRef.addGameId(builder, gameIdOffset);
+  RobotBlockRef.addSeat(builder, seat);
+  return RobotBlockRef.endRobotBlockRef(builder);
+}
+}

ui/src/gen/fbs/scrabblefb/target-request.ts

@@ -27,22 +27,34 @@ accountId(optionalEncoding?:any):string|Uint8Array|null {
   return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
 }
 
+gameId():string|null
+gameId(optionalEncoding:flatbuffers.Encoding):string|Uint8Array|null
+gameId(optionalEncoding?:any):string|Uint8Array|null {
+  const offset = this.bb!.__offset(this.bb_pos, 6);
+  return offset ? this.bb!.__string(this.bb_pos + offset, optionalEncoding) : null;
+}
+
 static startTargetRequest(builder:flatbuffers.Builder) {
-  builder.startObject(1);
+  builder.startObject(2);
 }
 
 static addAccountId(builder:flatbuffers.Builder, accountIdOffset:flatbuffers.Offset) {
   builder.addFieldOffset(0, accountIdOffset, 0);
 }
 
+static addGameId(builder:flatbuffers.Builder, gameIdOffset:flatbuffers.Offset) {
+  builder.addFieldOffset(1, gameIdOffset, 0);
+}
+
 static endTargetRequest(builder:flatbuffers.Builder):flatbuffers.Offset {
   const offset = builder.endObject();
   return offset;
 }
 
-static createTargetRequest(builder:flatbuffers.Builder, accountIdOffset:flatbuffers.Offset):flatbuffers.Offset {
+static createTargetRequest(builder:flatbuffers.Builder, accountIdOffset:flatbuffers.Offset, gameIdOffset:flatbuffers.Offset):flatbuffers.Offset {
   TargetRequest.startTargetRequest(builder);
   TargetRequest.addAccountId(builder, accountIdOffset);
+  TargetRequest.addGameId(builder, gameIdOffset);
   return TargetRequest.endTargetRequest(builder);
 }
 }

ui/src/lib/client.ts

@@ -6,6 +6,7 @@
 
 import type {
   AccountRef,
+  BlockList,
   BlockStatus,
   ChatMessage,
   EvalResult,
@@ -127,8 +128,8 @@ export interface GatewayClient {
   friendCodeRedeem(code: string): Promise<AccountRef>;
 
   // --- blocks ---
-  blocksList(): Promise<AccountRef[]>;
+  blocksList(): Promise<BlockList>;
-  block(accountId: string): Promise<void>;
+  block(accountId: string, gameId?: string): Promise<void>;
   unblock(accountId: string): Promise<void>;
 
   // --- invitations ---

ui/src/lib/codec.ts

@@ -9,6 +9,8 @@ import { indexForLetter, letterForIndex, setAlphabet, type AlphabetEntryWire } f
 import type { PlacedTile } from './client';
 import type {
   AccountRef,
+  BlockList,
+  RobotBlockEntry,
   Banner,
   BannerCampaign,
   BestMove,
@@ -576,11 +578,15 @@ export function decodeEvent(kind: string, payload: Uint8Array): PushEvent | null
 
 // --- social encoders ---
 
-export function encodeTarget(accountId: string): Uint8Array {
+export function encodeTarget(accountId: string, gameId?: string): Uint8Array {
   const b = new Builder(64);
   const id = b.createString(accountId);
+  // game_id is set only by an in-game block, so a disguised-robot opponent is recorded
+  // per-game; every other target path omits it.
+  const gid = gameId ? b.createString(gameId) : 0;
   fb.TargetRequest.startTargetRequest(b);
   fb.TargetRequest.addAccountId(b, id);
+  if (gid) fb.TargetRequest.addGameId(b, gid);
   return finish(b, fb.TargetRequest.endTargetRequest(b));
 }
 
@@ -722,14 +728,25 @@ export function decodeOutgoingList(buf: Uint8Array): AccountRef[] {
   return out;
 }
 
-export function decodeBlockList(buf: Uint8Array): AccountRef[] {
+export function decodeBlockList(buf: Uint8Array): BlockList {
   const l = fb.BlockList.getRootAsBlockList(new ByteBuffer(buf));
-  const out: AccountRef[] = [];
+  const blocked: AccountRef[] = [];
   for (let i = 0; i < l.blockedLength(); i++) {
     const r = l.blocked(i);
-    if (r) out.push(decodeAccountRef(r));
+    if (r) blocked.push(decodeAccountRef(r));
   }
-  return out;
+  const robots: RobotBlockEntry[] = [];
+  for (let i = 0; i < l.robotsLength(); i++) {
+    const r = l.robots(i);
+    if (r)
+      robots.push({
+        id: r.id() ?? '',
+        displayName: r.displayName() ?? '',
+        gameId: r.gameId() ?? '',
+        seat: r.seat(),
+      });
+  }
+  return { blocked, robots };
 }
 
 export function decodeFriendCode(buf: Uint8Array): FriendCode {

ui/src/lib/mock/client.ts

@@ -13,6 +13,7 @@ import type {
 import { GatewayError } from '../client';
 import type {
   AccountRef,
+  BlockList,
   BlockStatus,
   ChatMessage,
   EvalResult,
@@ -555,10 +556,13 @@ export class MockGateway implements GatewayClient {
   }
 
   // --- blocks ---
-  async blocksList(): Promise<AccountRef[]> {
+  async blocksList(): Promise<BlockList> {
-    return this.blocks.map((b) => ({ ...b }));
+    // The mock models human blocks only (no disguised robots); robots stays empty.
+    return { blocked: this.blocks.map((b) => ({ ...b })), robots: [] };
   }
-  async block(accountId: string): Promise<void> {
+  async block(accountId: string, _gameId?: string): Promise<void> {
+    // A block hides the blocked person from the blocker's own friends list (the real
+    // ListFriends filters them out), without deleting the underlying friendship.
     this.friends = this.friends.filter((f) => f.accountId !== accountId);
     if (!this.blocks.some((b) => b.accountId === accountId)) {
       this.blocks.push({ accountId, displayName: this.nameFor(accountId) });

ui/src/lib/model.ts

@@ -205,6 +205,22 @@ export interface AccountRef {
   displayName: string;
 }
 
+// RobotBlockEntry is one blocked disguised-robot opponent: a per-game record (not a real
+// account) carrying the game name the player saw and the game/seat it was blocked in. Its id
+// is used to unblock it.
+export interface RobotBlockEntry {
+  id: string;
+  displayName: string;
+  gameId: string;
+  seat: number;
+}
+
+// BlockList is the caller's blocked humans plus the per-game disguised-robot blocks.
+export interface BlockList {
+  blocked: AccountRef[];
+  robots: RobotBlockEntry[];
+}
+
 /** A freshly issued one-time friend code (the plaintext is returned once). */
 export interface FriendCode {
   code: string;

ui/src/lib/transport.ts

@@ -187,8 +187,8 @@ export function createTransport(baseUrl: string): GatewayClient {
     async blocksList() {
       return codec.decodeBlockList(await exec('blocks.list', codec.empty()));
     },
-    async block(accountId) {
+    async block(accountId, gameId) {
-      await exec('blocks.add', codec.encodeTarget(accountId));
+      await exec('blocks.add', codec.encodeTarget(accountId, gameId));
     },
     async unblock(accountId) {
       await exec('blocks.remove', codec.encodeTarget(accountId));

ui/src/screens/Friends.svelte

@@ -8,21 +8,27 @@
   import { translate } from '../lib/i18n/catalog';
   import { friendCodeParam, shareLink } from '../lib/deeplink';
   import { shareTelegramLink } from '../lib/telegram';
-  import type { AccountRef, FriendCode } from '../lib/model';
+  import type { AccountRef, FriendCode, RobotBlockEntry } from '../lib/model';
 
   let friends = $state<AccountRef[]>([]);
   let incoming = $state<AccountRef[]>([]);
   let blocked = $state<AccountRef[]>([]);
+  // Per-game disguised-robot blocks, shown as distinct entries alongside blocked humans.
+  let robotBlocks = $state<RobotBlockEntry[]>([]);
   let code = $state<FriendCode | null>(null);
   let redeemInput = $state('');
 
   async function load() {
     try {
-      [friends, incoming, blocked] = await Promise.all([
+      const [fl, inc, bl] = await Promise.all([
         gateway.friendsList(),
         gateway.friendsIncoming(),
         gateway.blocksList(),
       ]);
+      friends = fl;
+      incoming = inc;
+      blocked = bl.blocked;
+      robotBlocks = bl.robots;
     } catch (e) {
       handleError(e);
     }
@@ -179,7 +185,7 @@
       {/if}
     </section>
 
-    {#if blocked.length}
+    {#if blocked.length || robotBlocks.length}
       <section>
         <h3>{t('friends.blockedList')}</h3>
         {#each blocked as b (b.accountId)}
@@ -188,6 +194,12 @@
             <button class="ghost" onclick={() => unblock(b.accountId)} disabled={!connection.online}>{t('friends.unblock')}</button>
           </div>
         {/each}
+        {#each robotBlocks as r (r.id)}
+          <div class="item">
+            <span class="who">{r.displayName}</span>
+            <button class="ghost" onclick={() => unblock(r.id)} disabled={!connection.online}>{t('friends.unblock')}</button>
+          </div>
+        {/each}
       </section>
     {/if}
   {/if}