From 5db89edbc11d878aa804e311a421af19ac5ea0ed Mon Sep 17 00:00:00 2001
From: Eric Wagoner <ewagoner@gmail.com>
Date: Wed, 23 Sep 2026 18:48:53 -0400
Subject: [PATCH] Coordinates on the board, moves in the record shown on the
 board, a status strip above it with the capture in words, notes under the
 variant selector and a still that follows it, keyboard play, and a way back
 to the game from the rules

From a tester's review.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01Jm2auWk6RP71CjaAb4FMoG
---
 src/lib/components/Board.svelte     | 310 +++++++++++++++++++++-------
 src/lib/components/Hall.svelte      |  58 ++++--
 src/lib/game/index.ts               |  12 +-
 src/lib/game/spec.ts                |   3 +-
 src/routes/guide/+page.svelte       |  38 +++-
 src/routes/join/[code]/+page.svelte |   2 +-
 src/routes/rules/+page.svelte       |  13 +-
 7 files changed, 329 insertions(+), 107 deletions(-)

diff --git a/src/lib/components/Board.svelte b/src/lib/components/Board.svelte
index d7f3c21..4343d0b 100644
--- a/src/lib/components/Board.svelte
+++ b/src/lib/components/Board.svelte
@@ -1,10 +1,13 @@
 <script lang="ts">
-	// The board: a grid of squares, the pieces on them, and two taps to
-	// move. Copenhagen is fresh oak and clean stone; Tablut, the older game,
-	// is grey, bleached and a little uneven, by the tokens under data-set
-	// and a heavier grain and warp in the filters.
+	// The board: a grid of squares with coordinates on its edges, the pieces
+	// on them as tokens that slide and fade, and two taps or a keyboard to
+	// move. Above it, a strip says whose move it is and what the side is
+	// for; beside it, the record of moves, each one a click from being shown
+	// on the board. Copenhagen is fresh oak and clean stone; Tablut, the
+	// older game, is grey, bleached and a little uneven, by the tokens under
+	// data-set and a heavier grain and warp in the filters.
 	import TableTalk from './TableTalk.svelte';
-	import { cellOf, cornersOf, isEdge, movesFrom, rulesetOf, sideOf, throneOf, type Side } from '$lib/game';
+	import { beyond, cellOf, cornersOf, isEdge, movesFrom, rulesetOf, sideOf, throneOf, type Move, type Side } from '$lib/game';
 	import type { Room } from '$lib/net/room.svelte';
 
 	let { room }: { room: Room } = $props();
@@ -23,14 +26,28 @@
 	};
 	/** Linnaeus called the sides the Swedes and the Muscovites; Copenhagen calls them attackers and defenders. */
 	const sideWord = (side: Side) => (worn ? (side === 'attackers' ? 'the Muscovites' : 'the Swedes') : side === 'attackers' ? 'the attackers' : 'the defenders');
+	const sideName = (side: Side) => {
+		const w = sideWord(side);
+		return w.charAt(0).toUpperCase() + w.slice(1);
+	};
+	const objective = (side: Side) => (side === 'attackers' ? 'Take the king.' : set.escape === 'corner' ? 'Get the crowned king to a corner.' : 'Get the crowned king to any edge square.');
+	const sideOfPly = (ply: number): Side => (ply % 2 === 1 ? 'attackers' : 'defenders');
 
-	let selected = $state<number | null>(null);
-	const targets = $derived(selected === null ? [] : movesFrom(g, selected));
+	// --- Coordinates ---------------------------------------------------------
+	const CELL = 40;
+	const PAD_L = 16;
+	const PAD_T = 6;
+	const PAD_R = 6;
+	const PAD_B = 16;
+	const width = $derived(PAD_L + size * CELL + PAD_R);
+	const height = $derived(PAD_T + size * CELL + PAD_B);
+	const label = (i: number) => {
+		const c = cellOf(size, i);
+		return `${String.fromCharCode(97 + c.x)}${size - c.y}`;
+	};
+	const pieceWord = (p: string) => (p === 'k' ? 'the king' : p === 'a' ? 'an attacker' : 'a defender');
 
-	// Pieces are shown as tokens with a life of their own, so a move slides
-	// and a capture fades, one move at a time. The server's state may be
-	// two moves ahead (yours and the bot's answer); the tokens catch up
-	// move by move, with a beat between, so an exchange can be watched.
+	// --- Tokens: pieces with a life of their own, so a move slides and a capture fades ---
 	interface Token {
 		id: number;
 		piece: string;
@@ -70,6 +87,7 @@
 					tokens = tokens.filter((t) => !t.dying);
 				}
 				shown += 1;
+				announce(storyOf(shown));
 				if (shown < g.moves.length) await wait(260);
 			}
 		} finally {
@@ -83,37 +101,97 @@
 		else if (total > shown) void catchUp();
 	});
 
-	/** The move the tokens have just played, for the shaded squares. */
-	const shownLast = $derived(shown > 0 ? g.moves[shown - 1] : null);
+	// --- What the board shows: the last move played, or a move picked from the record ---
+	let reviewing = $state<number | null>(null);
+	$effect(() => {
+		void g.moves.length;
+		reviewing = null;
+		selected = null;
+	});
+	const shownPly = $derived(reviewing ?? shown);
+	const shownLast = $derived<Move | null>(shownPly > 0 ? g.moves[shownPly - 1] : null);
 	const shownSquares = $derived(shownLast ? [shownLast.from, shownLast.to] : []);
 	const shownCaptured = $derived(shownLast?.captured ?? []);
 
-	// A new position clears any half-made move.
-	$effect(() => {
-		void g.moves.length;
-		selected = null;
-	});
+	/** A move in words, and each capture as a trap: who took what, between which squares. */
+	function storyOf(ply: number): string {
+		const m = g.moves[ply - 1];
+		if (!m) return '';
+		const side = sideOfPly(ply);
+		const yours = !!mySide && mySide === side;
+		const who = yours ? 'You' : nameOfSide(side);
+		const moverPiece = ply === g.moves.length ? (g.cells[m.to] ?? '.') : '.';
+		const moverWord = moverPiece !== '.' ? pieceWord(moverPiece) : side === 'attackers' ? 'an attacker' : 'a piece';
+		let text = `${who}: ${moverWord} from ${label(m.from)} to ${label(m.to)}.`;
+		for (const c of m.captured) {
+			const anvil = beyond(size, m.to, c);
+			const kingFell = side === 'attackers' && !g.cells.includes('k') && ply === g.moves.length;
+			const victim = kingFell ? 'the king' : side === 'attackers' ? (yours ? 'a defender' : 'your defender') : yours ? 'an attacker' : 'your attacker';
+			const against =
+				anvil === -1
+					? 'the edge'
+					: corners.includes(anvil)
+						? `the corner at ${label(anvil)}`
+						: anvil === throne && g.cells[anvil] === '.'
+							? `the empty throne at ${label(anvil)}`
+							: `${label(anvil)}`;
+			text += ` ${victim.charAt(0).toUpperCase() + victim.slice(1)} on ${label(c)} was trapped between ${label(m.to)} and ${against}.`;
+		}
+		return text;
+	}
+	const shownStory = $derived(shownPly > 0 ? storyOf(shownPly) : '');
+
+	// --- Choosing and moving ---------------------------------------------------
+	let selected = $state<number | null>(null);
+	const targets = $derived(selected === null ? [] : movesFrom(g, selected));
+	let liveText = $state('');
+	function announce(text: string) {
+		liveText = text;
+	}
 
 	async function tap(i: number) {
 		if (!yourMove || room.sending || animating) return;
+		reviewing = null;
 		if (selected !== null && targets.includes(i)) {
 			const from = selected;
 			selected = null;
 			await room.submit({ from, to: i });
 			return;
 		}
-		if (sideOf(g.cells[i]) === mySide) selected = selected === i ? null : i;
-		else selected = null;
+		if (sideOf(g.cells[i]) === mySide) {
+			selected = selected === i ? null : i;
+			if (selected !== null) {
+				const to = movesFrom(g, i);
+				announce(`Selected ${pieceWord(g.cells[i])} on ${label(i)}. ${to.length} ${to.length === 1 ? 'square' : 'squares'} to move to${to.length ? ': ' + to.map(label).join(', ') : ''}.`);
+			} else announce('Selection cleared.');
+		} else selected = null;
 	}
 
-	const CELL = 40;
-	const PAD = 6;
-	const span = $derived(size * CELL + PAD * 2);
-	const label = (i: number) => {
+	function focusSquare(i: number) {
+		document.querySelector<SVGRectElement>(`rect.square[data-i="${i}"]`)?.focus();
+	}
+
+	function key(e: KeyboardEvent, i: number) {
 		const c = cellOf(size, i);
-		return `${String.fromCharCode(97 + c.x)}${size - c.y}`;
-	};
-	const pieceWord = (p: string) => (p === 'k' ? 'the king' : p === 'a' ? 'an attacker' : 'a defender');
+		const step: Record<string, [number, number]> = { ArrowLeft: [-1, 0], ArrowRight: [1, 0], ArrowUp: [0, -1], ArrowDown: [0, 1] };
+		if (e.key in step) {
+			e.preventDefault();
+			const [dx, dy] = step[e.key];
+			const x = c.x + dx;
+			const y = c.y + dy;
+			if (x >= 0 && y >= 0 && x < size && y < size) focusSquare(y * size + x);
+			return;
+		}
+		if (e.key === 'Enter' || e.key === ' ') {
+			e.preventDefault();
+			void tap(i);
+		} else if (e.key === 'Escape') {
+			selected = null;
+			reviewing = null;
+			announce('Selection cleared.');
+		}
+	}
+
 	const verdict = $derived.by(() => {
 		if (!g.over) return '';
 		if (g.over.winner === null) return 'A draw.';
@@ -123,8 +201,24 @@
 
 <main class="board" data-set={set.id}>
 	<section class="play">
+		<div class="status" class:yours={yourMove}>
+			{#if g.over}
+				<strong>{verdict}</strong> <span class="muted">{g.over.reason}</span>
+			{:else if room.spectating}
+				<strong>{nameOfSide(g.toMove)} to move</strong> · {sideName(g.toMove)} · <span class="muted">turn {g.moves.length + 1}</span>
+			{:else if yourMove}
+				<strong>Your move</strong> · {sideName(mySide!)} · <span class="goal">{objective(mySide!)}</span>
+			{:else}
+				<strong>{nameOfSide(g.toMove)} is thinking</strong> · you are {sideWord(mySide!)} · <span class="goal">{objective(mySide!)}</span>
+			{/if}
+		</div>
+		{#if shownStory && (shownCaptured.length || reviewing !== null)}
+			<p class="story" class:capture={shownCaptured.length > 0}>{shownStory}{#if reviewing !== null}&nbsp;<button type="button" class="link" onclick={() => (reviewing = null)}>back to now</button>{/if}</p>
+		{/if}
+		{#if room.error}<p class="warning">{room.error}</p>{/if}
+
 		<div class="frame">
-			<svg viewBox="0 0 {span} {span}" role="grid" aria-label="The board">
+			<svg viewBox="0 0 {width} {height}" role="grid" aria-label="The board">
 				<defs>
 					<filter id="grain" x="0" y="0" width="100%" height="100%">
 						<feTurbulence type="fractalNoise" baseFrequency="0.9" numOctaves="2" seed="7" result="noise" />
@@ -137,12 +231,16 @@
 						<feDisplacementMap in="SourceGraphic" in2="warp" scale={worn ? 2.4 : 0} xChannelSelector="R" yChannelSelector="G" />
 					</filter>
 				</defs>
-				<rect class="wood" x="0" y="0" width={span} height={span} rx="6" filter="url(#grain)" />
+				<rect class="wood" x="0" y="0" {width} {height} rx="6" filter="url(#grain)" />
+				{#each Array.from({ length: size }, (_, n) => n) as n (n)}
+					<text class="coord" x={PAD_L + n * CELL + CELL / 2} y={height - 4} text-anchor="middle">{String.fromCharCode(97 + n)}</text>
+					<text class="coord" x={PAD_L - 4} y={PAD_T + n * CELL + CELL / 2 + 3} text-anchor="end">{size - n}</text>
+				{/each}
 				<g filter="url(#worn)">
 					{#each g.cells as piece, i (i)}
 						{@const c = cellOf(size, i)}
-						{@const x = PAD + c.x * CELL}
-						{@const y = PAD + c.y * CELL}
+						{@const x = PAD_L + c.x * CELL}
+						{@const y = PAD_T + c.y * CELL}
 						<rect
 							class="square"
 							class:throne={i === throne}
@@ -151,20 +249,17 @@
 							class:target={targets.includes(i)}
 							class:fallen={shownCaptured.includes(i)}
 							class:edge={set.escape === 'edge' && isEdge(size, i)}
+							data-i={i}
 							{x}
 							{y}
 							width={CELL}
 							height={CELL}
 							role="gridcell"
-							aria-label={`${label(i)}${piece === '.' ? '' : `, ${pieceWord(piece)}`}`}
+							aria-label={`${label(i)}${piece === '.' ? '' : `, ${pieceWord(piece)}`}${targets.includes(i) ? ', a legal move' : ''}`}
+							aria-selected={selected === i}
 							tabindex={yourMove ? 0 : -1}
 							onclick={() => tap(i)}
-							onkeydown={(e) => {
-								if (e.key === 'Enter' || e.key === ' ') {
-									e.preventDefault();
-									tap(i);
-								}
-							}}
+							onkeydown={(e) => key(e, i)}
 						/>
 						{#if targets.includes(i)}
 							<circle class="hint" cx={x + CELL / 2} cy={y + CELL / 2} r={CELL * 0.14} pointer-events="none" />
@@ -172,8 +267,8 @@
 					{/each}
 					{#each tokens as t (t.id)}
 						{@const c = cellOf(size, t.at)}
-						{@const cx = PAD + c.x * CELL + CELL / 2}
-						{@const cy = PAD + c.y * CELL + CELL / 2}
+						{@const cx = PAD_L + c.x * CELL + CELL / 2}
+						{@const cy = PAD_T + c.y * CELL + CELL / 2}
 						<g
 							class="piece {t.piece === 'a' ? 'attacker' : t.piece === 'k' ? 'king' : 'defender'}"
 							class:selected={selected === t.at}
@@ -191,27 +286,14 @@
 				</g>
 			</svg>
 		</div>
+		<p class="visually-hidden" aria-live="polite">{liveText}</p>
 
 		{#if g.over}
 			<div class="verdict">
-				<h2>{verdict}</h2>
-				<p>{g.over.reason}</p>
 				<a class="commit" href="/">Back to the hall</a>
 			</div>
-		{:else if room.spectating}
-			<section class="move">
-				<h2>You watch from the Peanut Gallery</h2>
-				<p class="muted">{nameOfSide(g.toMove)}, {sideWord(g.toMove)}, to move. Turn {g.moves.length + 1}.</p>
-			</section>
-		{:else}
-			<section class="move">
-				<h2>{yourMove ? 'Your move' : `Waiting on ${nameOfSide(g.toMove)}`}</h2>
-				<p class="muted">
-					You play {sideWord(mySide!)}: {mySide === 'attackers' ? 'take the king.' : set.escape === 'corner' ? 'bring the king to a corner.' : 'bring the king to the edge.'}
-					{#if yourMove}Tap a piece, then a square.{/if}
-				</p>
-				{#if room.error}<p class="warning">{room.error}</p>{/if}
-			</section>
+		{:else if yourMove}
+			<p class="muted small how">Tap a piece, then a square. With a keyboard: arrows to move about the board, Enter to pick up and to set down, Escape to cancel.</p>
 		{/if}
 	</section>
 
@@ -227,13 +309,17 @@
 					</li>
 				{/each}
 			</ul>
-			<p class="muted small">Turn {g.moves.length + 1}.</p>
+			<p class="muted small">Turn {g.moves.length + 1}.{#if g.moves.length}&nbsp;Click a move to see it on the board.{/if}</p>
 			{#if g.moves.length}
 				<ol class="record muted small" reversed start={g.moves.length}>
-					{#each g.moves.slice(-6).reverse() as m, i (g.moves.length - i)}
+					{#each g.moves.slice(-8).reverse() as m, i (g.moves.length - i)}
 						{@const ply = g.moves.length - i}
-						{@const side = ply % 2 === 1 ? 'attackers' : 'defenders'}
-						<li class:mine={mySide === side}>{nameOfSide(side)}: {label(m.from)} to {label(m.to)}{#if m.captured.length}, <strong>taking {m.captured.map(label).join(', ')}</strong>{/if}</li>
+						{@const side = sideOfPly(ply)}
+						<li class:mine={mySide === side} class:reviewed={reviewing === ply}>
+							<button type="button" class="link" onclick={() => (reviewing = reviewing === ply ? null : ply)}>
+								{nameOfSide(side)}: {label(m.from)} to {label(m.to)}{#if m.captured.length}, <strong>taking {m.captured.map(label).join(', ')}</strong>{/if}
+							</button>
+						</li>
 					{/each}
 				</ol>
 			{/if}
@@ -253,6 +339,7 @@
 		/* Copenhagen: fresh oak, clean stone. */
 		--wood: #8a5a2b;
 		--wood-line: rgba(30, 16, 6, 0.55);
+		--coord: rgba(255, 240, 210, 0.55);
 		--square: rgba(255, 240, 210, 0.08);
 		--square-edge: rgba(255, 250, 235, 0.11);
 		--throne: rgba(240, 165, 58, 0.35);
@@ -270,6 +357,7 @@
 	.board[data-set='tablut'] {
 		--wood: #8d8577;
 		--wood-line: rgba(40, 34, 28, 0.4);
+		--coord: rgba(30, 26, 20, 0.5);
 		--square: rgba(255, 250, 235, 0.05);
 		--square-edge: rgba(255, 250, 235, 0.09);
 		--throne: rgba(120, 100, 70, 0.4);
@@ -289,6 +377,48 @@
 		}
 	}
 
+	.status {
+		max-width: 620px;
+		margin: 0 auto 0.5rem;
+		padding: 0.45rem 0.8rem;
+		border: 1px solid var(--rule);
+		border-radius: 6px;
+		font-size: 0.95rem;
+		color: var(--bone-dim);
+	}
+
+	.status strong {
+		color: var(--bone);
+	}
+
+	.status.yours {
+		border-color: var(--ember);
+	}
+
+	.status.yours strong {
+		color: var(--ember);
+	}
+
+	.goal {
+		color: var(--bone);
+	}
+
+	.story {
+		max-width: 620px;
+		margin: 0 auto 0.5rem;
+		font-size: 0.9rem;
+		color: var(--bone-dim);
+	}
+
+	.story.capture {
+		color: var(--bone);
+	}
+
+	.warning {
+		max-width: 620px;
+		margin: 0 auto 0.5rem;
+	}
+
 	.frame {
 		max-width: 620px;
 		margin: 0 auto;
@@ -305,6 +435,13 @@
 		transition: fill 1.2s ease;
 	}
 
+	.coord {
+		fill: var(--coord);
+		font-family: var(--font);
+		font-size: 9px;
+		pointer-events: none;
+	}
+
 	.square {
 		fill: var(--square);
 		stroke: var(--wood-line);
@@ -340,7 +477,7 @@
 	.square:focus-visible {
 		outline: none;
 		stroke: var(--frost);
-		stroke-width: 2;
+		stroke-width: 2.5;
 	}
 
 	.hint {
@@ -364,7 +501,9 @@
 
 	.piece .body {
 		stroke-width: 2;
-		transition: fill 1.2s ease, stroke 1.2s ease;
+		transition:
+			fill 1.2s ease,
+			stroke 1.2s ease;
 	}
 
 	.piece.attacker .body {
@@ -391,20 +530,14 @@
 		stroke-width: 3;
 	}
 
-	.move,
+	.how {
+		max-width: 620px;
+		margin: 0.5rem auto 0;
+	}
+
 	.verdict {
-		margin-top: 1rem;
-	}
-
-	.move h2,
-	.verdict h2 {
-		font-size: 1.4rem;
-		margin-bottom: 0.3rem;
-	}
-
-	.verdict .commit {
-		display: inline-block;
-		margin-top: 0.6rem;
+		max-width: 620px;
+		margin: 0.8rem auto 0;
 	}
 
 	.sides h2 {
@@ -462,8 +595,35 @@
 		color: var(--bone);
 	}
 
+	.record li.reviewed .link {
+		color: var(--frost);
+	}
+
 	.record strong {
 		color: var(--ember);
 		font-weight: 500;
 	}
+
+	.link {
+		background: none;
+		border: 0;
+		padding: 0;
+		font: inherit;
+		color: inherit;
+		cursor: pointer;
+		text-align: left;
+	}
+
+	.link:hover {
+		text-decoration: underline;
+	}
+
+	.visually-hidden {
+		position: absolute;
+		width: 1px;
+		height: 1px;
+		overflow: hidden;
+		clip: rect(0 0 0 0);
+		white-space: nowrap;
+	}
 </style>
diff --git a/src/lib/components/Hall.svelte b/src/lib/components/Hall.svelte
index da6ebe5..437355d 100644
--- a/src/lib/components/Hall.svelte
+++ b/src/lib/components/Hall.svelte
@@ -15,6 +15,16 @@
 	let code = $state('');
 	/** The host's choices for the next table, from the game's declared options. */
 	let options = $state<Record<string, string>>(Object.fromEntries((game.options ?? []).map((o) => [o.key, o.default])));
+
+	/** The hall's still of the opening position, on whichever board the selector names. */
+	const still = $derived(
+		options.set === 'tablut'
+			? { n: 9, wood: '#8d8577', line: 'rgba(40,34,28,0.5)', dark: '#3d3530', darkRim: '#1c1714', pale: '#cfc4ad', paleRim: '#8c8069', king: '#c9b27a', kingRim: '#7d6636', corners: false,
+				a: [[3,0],[4,0],[5,0],[4,1],[0,3],[8,3],[0,4],[1,4],[7,4],[8,4],[0,5],[8,5],[4,7],[3,8],[4,8],[5,8]], d: [[4,2],[4,3],[2,4],[3,4],[5,4],[6,4],[4,5],[4,6]] }
+			: { n: 11, wood: '#8a5a2b', line: 'rgba(30,16,6,0.5)', dark: '#2a2320', darkRim: '#0d0a08', pale: '#ece4d0', paleRim: '#b9ab8b', king: '#f0d58a', kingRim: '#a67c1a', corners: true,
+				a: [[3,0],[4,0],[5,0],[6,0],[7,0],[5,1],[0,3],[10,3],[0,4],[10,4],[0,5],[1,5],[9,5],[10,5],[0,6],[10,6],[0,7],[10,7],[5,9],[3,10],[4,10],[5,10],[6,10],[7,10]], d: [[5,3],[4,4],[5,4],[6,4],[3,5],[4,5],[6,5],[7,5],[4,6],[5,6],[6,6],[5,7]] }
+	);
+	const mid = $derived((still.n - 1) / 2);
 	let busy = $state(false);
 	let error = $state('');
 	let seats = $state(allSeats());
@@ -156,7 +166,7 @@
 	<div class="lid-head">
 		<h1>Hnefatafl</h1>
 		<p class="pitch">The Viking board game. One king, one throne, four corners, and a ring of attackers closing in.</p>
-		<p class="tag">Hnefatafl was played across the Norse world for a thousand years before chess. Every piece moves like a rook and is taken by being sandwiched; the attackers must capture the king, the king must reach a corner. Play a housecarl, or open a table for a friend and play by turns. Copenhagen rules on the big board, or Tablut, the older game Linnaeus wrote down in 1732.</p>
+		<p class="tag">Hnefatafl was played across the Norse world for a thousand years before chess. Every piece moves like a rook and is taken by being sandwiched; the attackers must capture the king, the king must reach safety. Play a housecarl, or open a table for a friend and play by turns. Copenhagen rules on the big board, or Tablut, the older game Linnaeus wrote down in 1732.</p>
 		<p class="links"><a href="/guide">how to play</a> · <a href="/rules">the rules</a> · <a class="about-link" href="#about" onclick={() => (aboutOpen = true)}>about this game — a labor of love</a></p>
 	</div>
 
@@ -168,12 +178,16 @@
 		{#if game.options?.length}
 			<div class="options">
 				{#each game.options as o (o.key)}
-					<label class="option">
-						<span>{o.label}</span>
-						<select bind:value={options[o.key]}>
-							{#each o.choices as c (c.value)}<option value={c.value}>{c.label}</option>{/each}
-						</select>
-					</label>
+					{@const chosen = o.choices.find((c) => c.value === options[o.key])}
+					<div class="option-block">
+						<label class="option">
+							<span>{o.label}</span>
+							<select bind:value={options[o.key]}>
+								{#each o.choices as c (c.value)}<option value={c.value}>{c.label}</option>{/each}
+							</select>
+						</label>
+						{#if chosen?.note}<p class="option-note muted small">{chosen.note}</p>{/if}
+					</div>
 				{/each}
 			</div>
 		{/if}
@@ -196,20 +210,20 @@
 	</div>
 
 	<div class="lid-look" aria-hidden="true">
-		<svg class="still" viewBox="0 0 110 110" aria-hidden="true">
-			<rect x="0" y="0" width="110" height="110" rx="4" fill="#8a5a2b" />
-			{#each Array.from({ length: 11 }, (_, r) => r) as r (r)}
-				{#each Array.from({ length: 11 }, (_, c) => c) as c (c)}
-					<rect x={c * 10} y={r * 10} width="10" height="10" fill={(r === 0 || r === 10) && (c === 0 || c === 10) ? 'rgba(224,101,92,0.4)' : r === 5 && c === 5 ? 'rgba(240,165,58,0.4)' : 'rgba(255,240,210,0.08)'} stroke="rgba(30,16,6,0.5)" stroke-width="0.4" />
+		<svg class="still" class:worn={options.set === 'tablut'} viewBox="0 0 {still.n * 10} {still.n * 10}" aria-hidden="true">
+			<rect x="0" y="0" width={still.n * 10} height={still.n * 10} rx="4" fill={still.wood} />
+			{#each Array.from({ length: still.n }, (_, r) => r) as r (r)}
+				{#each Array.from({ length: still.n }, (_, c) => c) as c (c)}
+					<rect x={c * 10} y={r * 10} width="10" height="10" fill={still.corners && (r === 0 || r === still.n - 1) && (c === 0 || c === still.n - 1) ? 'rgba(224,101,92,0.4)' : r === mid && c === mid ? 'rgba(240,165,58,0.4)' : 'rgba(255,240,210,0.08)'} stroke={still.line} stroke-width="0.4" />
 				{/each}
 			{/each}
-			{#each [[3,0],[4,0],[5,0],[6,0],[7,0],[5,1],[0,3],[10,3],[0,4],[10,4],[0,5],[1,5],[9,5],[10,5],[0,6],[10,6],[0,7],[10,7],[5,9],[3,10],[4,10],[5,10],[6,10],[7,10]] as [x, y] (`${x},${y}`)}
-				<circle cx={x * 10 + 5} cy={y * 10 + 5} r="3.4" fill="#2a2320" stroke="#0d0a08" stroke-width="0.6" />
+			{#each still.a as [x, y] (`${x},${y}`)}
+				<circle cx={x * 10 + 5} cy={y * 10 + 5} r="3.4" fill={still.dark} stroke={still.darkRim} stroke-width="0.6" />
 			{/each}
-			{#each [[5,3],[4,4],[5,4],[6,4],[3,5],[4,5],[6,5],[7,5],[4,6],[5,6],[6,6],[5,7]] as [x, y] (`${x},${y}`)}
-				<circle cx={x * 10 + 5} cy={y * 10 + 5} r="3.4" fill="#ece4d0" stroke="#b9ab8b" stroke-width="0.6" />
+			{#each still.d as [x, y] (`${x},${y}`)}
+				<circle cx={x * 10 + 5} cy={y * 10 + 5} r="3.4" fill={still.pale} stroke={still.paleRim} stroke-width="0.6" />
 			{/each}
-			<circle cx="55" cy="55" r="3.6" fill="#f0d58a" stroke="#a67c1a" stroke-width="0.6" />
+			<circle cx={mid * 10 + 5} cy={mid * 10 + 5} r="3.6" fill={still.king} stroke={still.kingRim} stroke-width="0.6" />
 		</svg>
 	</div>
 
@@ -609,12 +623,22 @@
 		gap: 0.5rem;
 		font-size: 0.9rem;
 	}
+
+	.option-note {
+		margin: 0.2rem 0 0;
+		max-width: 22em;
+	}
 	.still {
 		width: 100%;
 		max-width: 18rem;
 		display: block;
 		margin: 0 auto;
 		border-radius: 4px;
+		transition: filter 0.9s ease;
+	}
+
+	.still.worn {
+		filter: contrast(0.85) sepia(0.15);
 	}
 	.tally {
 		display: grid;
diff --git a/src/lib/game/index.ts b/src/lib/game/index.ts
index fb4bce8..b204311 100644
--- a/src/lib/game/index.ts
+++ b/src/lib/game/index.ts
@@ -44,9 +44,9 @@ export interface State {
 
 export type Input = { from: number; to: number };
 
-export const SIDES: { value: Side; label: string }[] = [
-	{ value: 'defenders', label: 'the defenders, with the king' },
-	{ value: 'attackers', label: 'the attackers' }
+export const SIDES: { value: Side; label: string; note: string }[] = [
+	{ value: 'defenders', label: 'the defenders, with the king', note: 'Fewer pieces, and the king must reach safety before the ring closes.' },
+	{ value: 'attackers', label: 'the attackers', note: 'Twice the pieces, and the first move; close every road and take the king.' }
 ];
 
 // --- The board ---------------------------------------------------------------
@@ -91,7 +91,7 @@ function neighbors(size: number, i: number): number[] {
 }
 
 /** The square on the far side of `mid` from `from`, or -1 off the board. */
-function beyond(size: number, from: number, mid: number): number {
+export function beyond(size: number, from: number, mid: number): number {
 	const a = cellOf(size, from);
 	const b = cellOf(size, mid);
 	const c = { x: b.x + (b.x - a.x), y: b.y + (b.y - a.y) };
@@ -390,8 +390,8 @@ export const game: GameSpec<State, Input> = {
 			key: 'set',
 			label: 'Rules',
 			choices: [
-				{ value: 'copenhagen', label: 'Copenhagen, 11 by 11' },
-				{ value: 'tablut', label: 'Tablut, 9 by 9, after Linnaeus' }
+				{ value: 'copenhagen', label: 'Copenhagen, 11 by 11', note: 'The modern tournament game. The king escapes to a corner and falls only to four attackers, three beside the throne.' },
+				{ value: 'tablut', label: 'Tablut, 9 by 9, after Linnaeus', note: 'The older game. The king escapes to any edge square, and away from the throne two attackers take him like any piece.' }
 			],
 			default: 'copenhagen'
 		},
diff --git a/src/lib/game/spec.ts b/src/lib/game/spec.ts
index 5be71f4..dd5c4fe 100644
--- a/src/lib/game/spec.ts
+++ b/src/lib/game/spec.ts
@@ -25,7 +25,8 @@ export interface Outcome {
 export interface TableOption {
 	key: string;
 	label: string;
-	choices: { value: string; label: string }[];
+	/** A choice's note is shown under the selector while it is chosen: the one line a player needs to pick. */
+	choices: { value: string; label: string; note?: string }[];
 	/** The value a table gets when the host chooses nothing. */
 	default: string;
 }
diff --git a/src/routes/guide/+page.svelte b/src/routes/guide/+page.svelte
index 8278da1..1176922 100644
--- a/src/routes/guide/+page.svelte
+++ b/src/routes/guide/+page.svelte
@@ -12,7 +12,7 @@
 		<h1>How to play</h1>
 		<p class="lede">A walk through the page, from the hall to a first game. The game's own rules are on <a href="/rules">the rules page</a>.</p>
 		<nav>
-			<a href="#hall">The hall</a> · <a href="#table">The table</a> · <a href="#board">The board</a> · <a href="#gallery">The Peanut Gallery and table talk</a> ·
+			<a href="#hall">The hall</a> · <a href="#table">The table</a> · <a href="#board">The board</a> · <a href="#capture">A capture</a> · <a href="#gallery">The Peanut Gallery and table talk</a> ·
 			<a href="#first">A first game</a>
 		</nav>
 	</header>
@@ -37,12 +37,27 @@
 	<section id="board">
 		<h2>The board</h2>
 		<p>
-			Tap one of your pieces and its reachable squares light up; tap a square to move there. The last move is shaded, and a square a piece was just taken from shows red for a
-			moment. The attackers are the dark pieces and move first; the defenders are the pale pieces around the crowned king on the throne. In Copenhagen the four corners are marked:
+			Tap one of your pieces and its reachable squares light up; tap a square to move there. The last move is shaded, a square a piece was just taken from shows red until the next
+			move, and the strip above the board says whose move it is and what your side is for. The record beside the board lists the moves; click one to see it on the board. The attackers are the dark pieces and move first; the defenders are the pale pieces around the crowned king on the throne. In Copenhagen the four corners are marked:
 			only the king may enter them, and reaching one wins. In Tablut the board is older and plainer, and the king needs only the edge.
 		</p>
 	</section>
 
+	<section id="capture">
+		<h2>How a capture works</h2>
+		<figure class="capture">
+			<svg viewBox="0 0 90 30" aria-label="An attacker moves beside a defender that already has an attacker on its other side; the defender is taken.">
+				<rect width="90" height="30" rx="2" fill="#8a5a2b" />
+				{#each [0, 1, 2] as c (c)}<rect x={c * 30} y="0" width="30" height="30" fill="rgba(255,240,210,0.08)" stroke="rgba(30,16,6,0.5)" stroke-width="0.6" />{/each}
+				<circle cx="15" cy="15" r="9" fill="#2a2320" stroke="#0d0a08" stroke-width="1.2" />
+				<circle cx="45" cy="15" r="9" fill="#ece4d0" stroke="#b9ab8b" stroke-width="1.2" opacity="0.5" />
+				<circle cx="75" cy="15" r="9" fill="#2a2320" stroke="#0d0a08" stroke-width="1.2" />
+				<path d="M62 4 h11 l-3 -3 m3 3 l-3 3" fill="none" stroke="#9cd0dc" stroke-width="1.4" />
+			</svg>
+			<figcaption>The right-hand attacker arrives; the pale defender is caught between two enemies and is taken. Only the mover captures: a piece may step into that gap safely on its own turn.</figcaption>
+		</figure>
+	</section>
+
 	<section id="gallery">
 		<h2>The Peanut Gallery and table talk</h2>
 		<p>
@@ -99,6 +114,23 @@
 		margin-bottom: 0.4rem;
 	}
 
+	.capture {
+		margin: 0.6rem 0 0;
+	}
+
+	.capture svg {
+		width: 12rem;
+		display: block;
+		border-radius: 3px;
+	}
+
+	.capture figcaption {
+		margin-top: 0.5rem;
+		font-size: 0.9rem;
+		color: var(--bone-dim);
+		max-width: 38em;
+	}
+
 	.word {
 		margin-top: 2rem;
 		color: var(--bone-dim);
diff --git a/src/routes/join/[code]/+page.svelte b/src/routes/join/[code]/+page.svelte
index 34c7abb..6bbb509 100644
--- a/src/routes/join/[code]/+page.svelte
+++ b/src/routes/join/[code]/+page.svelte
@@ -121,7 +121,7 @@
 			{/if}
 		{/if}
 		<a class="quiet" href="/guide">How to play</a>
-		<a class="quiet" href="/rules">Rules</a>
+		<a class="quiet" href={room ? `/rules?room=${roomId}` : '/rules'}>Rules</a>
 		{#if room}
 			<button type="button" class="quiet" title="Something behaved unexpectedly? Tell the keeper." onclick={() => (reporting = true)}>Report</button>
 		{/if}
diff --git a/src/routes/rules/+page.svelte b/src/routes/rules/+page.svelte
index e9ae281..4bc2cf4 100644
--- a/src/routes/rules/+page.svelte
+++ b/src/routes/rules/+page.svelte
@@ -1,6 +1,10 @@
 <script lang="ts">
 	// The rules page: Copenhagen as this table plays it, then Tablut and the
 	// gaps in Linnaeus that every reconstruction fills for itself.
+	import { page } from '$app/state';
+
+	/** Opened from a table, the page offers the way back to it. */
+	const room = $derived((page.url.searchParams.get('room') ?? '').toUpperCase());
 </script>
 
 <svelte:head>
@@ -9,7 +13,7 @@
 
 <main class="rules">
 	<header>
-		<a class="back" href="/">Back to the hall</a> · <a class="back" href="/guide">How to play</a>
+		{#if room}<a class="back" href={`/join/${room}`}>Back to your game</a> · {/if}<a class="back" href="/">Back to the hall</a> · <a class="back" href="/guide">How to play</a>
 		<h1>The rules</h1>
 		<p class="lede">
 			Hnefatafl is the tafl family's best-known member: a Viking board game played across Scandinavia and the North Atlantic from the fourth century until chess displaced it. No
@@ -30,8 +34,9 @@
 	<section id="moving">
 		<h2>Moving</h2>
 		<p>
-			Every piece moves like a rook in chess: any number of empty squares along a row or column, never diagonally, never over another piece. Only the king may stop on the throne
-			or on a corner square. In Copenhagen an ordinary piece may pass across the empty throne; in Tablut it may not.
+			Every piece moves like a rook in chess: any number of empty squares along a row or column, never diagonally, never over another piece. Only the king may stop on the throne, and
+			in Copenhagen only the king may enter the four marked corners; in Tablut the corners are ordinary squares. In Copenhagen an ordinary piece may pass across the empty throne;
+			in Tablut it may not.
 		</p>
 	</section>
 
@@ -39,7 +44,7 @@
 		<h2>Capturing</h2>
 		<p>
 			A piece is captured when the moving piece closes it between itself and another enemy piece on the opposite side, along a row or column. A piece may safely move between two
-			enemies: only the mover captures. The four corners and the empty throne stand in for an enemy piece, so a piece pinned against one of them by a single enemy is taken. The
+			enemies: only the mover captures. The empty throne stands in for an enemy piece, and in Copenhagen so do the four marked corners, so a piece pinned against one of them by a single enemy is taken. The
 			king takes part in captures like any piece.
 		</p>
 		<p>