diff --git a/app/components/Settings/BottomScreen/Menus/Options/GbaMode.vue b/app/components/Settings/BottomScreen/Menus/Options/GbaMode.vue
index b041d5e..eeabc82 100644
--- a/app/components/Settings/BottomScreen/Menus/Options/GbaMode.vue
+++ b/app/components/Settings/BottomScreen/Menus/Options/GbaMode.vue
@@ -1,13 +1,254 @@
 <script setup lang="ts">
+// TODO: store state in local storage
+
+const store = useSettingsStore();
+const confirmationModal = useConfirmationModal();
+const { assets } = useAssets();
 const { onRender } = useScreen();
 
+const handleActivateB = () => {
+  store.closeSubMenu();
+};
+
+const handleActivateA = () => {
+  if (isDead()) {
+    resetBoard();
+    confirmationModal.close();
+    return;
+  }
+  confirmationModal.open({
+    text: "Restart game?",
+    onConfirm: () => {
+      resetBoard();
+      confirmationModal.close();
+    },
+    onCancel: () => {
+      confirmationModal.close();
+    },
+  });
+};
+
+const TILE_COLORS: Record<number, { bg: string; fg: string }> = {
+  [0]: { bg: "#ccc0b4", fg: "#776e65" },
+  [2]: { bg: "#eee4db", fg: "#776e65" },
+  [4]: { bg: "#eee0cb", fg: "#776e65" },
+  [8]: { bg: "#f3b27a", fg: "#f9f6f2" },
+  [16]: { bg: "#f69664", fg: "#f9f6f2" },
+  [32]: { bg: "#f67c5f", fg: "#f9f6f2" },
+  [64]: { bg: "#f7603c", fg: "#f9f6f2" },
+  [128]: { bg: "#ecd072", fg: "#f9f6f2" },
+  [256]: { bg: "#eecc62", fg: "#f9f6f2" },
+  [512]: { bg: "#eec950", fg: "#f9f6f2" },
+  [1024]: { bg: "#edc53f", fg: "#f9f6f2" },
+  [2048]: { bg: "#edc12e", fg: "#f9f6f2" },
+  [4046]: { bg: "#3c3a33", fg: "#f9f6f2" },
+};
+const LAST_TILE_COLOR =
+  Object.values(TILE_COLORS)[Object.values(TILE_COLORS).length - 1]!;
+const TILE_SIZE = 28;
+
+const BORDER_COLOR = "#bbada0";
+const BORDER_SIZE = 3;
+
+const BOARD_X = 64;
+const BOARD_Y = 32;
+const BOARD_SIZE = 4;
+
+const board = Array.from({ length: BOARD_SIZE }, () =>
+  Array.from({ length: BOARD_SIZE }, () => 0),
+);
+
 onRender((ctx) => {
+  assets.images.home.topScreen.background.draw(ctx, 0, 0);
+
   ctx.font = "10px NDS10";
-  ctx.fillStyle = "#000000";
-  ctx.fillText("GBA Mode", 10, 20);
+  ctx.textBaseline = "top";
+
+  ctx.translate(BOARD_X, BOARD_Y);
+
+  ctx.fillStyle = BORDER_COLOR;
+  ctx.fillRect(
+    0,
+    0,
+    BORDER_SIZE * (BOARD_SIZE + 1) + TILE_SIZE * BOARD_SIZE,
+    BORDER_SIZE * (BOARD_SIZE + 1) + TILE_SIZE * BOARD_SIZE,
+  );
+
+  const renderTile = (col: number, row: number) => {
+    const value = board[row]![col]!;
+    const color = TILE_COLORS[value] ?? LAST_TILE_COLOR;
+
+    const x = BORDER_SIZE + col * (TILE_SIZE + BORDER_SIZE);
+    const y = BORDER_SIZE + row * (TILE_SIZE + BORDER_SIZE);
+
+    ctx.fillStyle = color.bg;
+    ctx.fillRect(x, y, TILE_SIZE, TILE_SIZE);
+
+    if (value === 0) return;
+
+    ctx.fillStyle = color.fg;
+    ctx.font = value <= 2048 ? "10px NDS10" : "7px NDS7";
+    fillTextHCentered(
+      ctx,
+      value.toString(),
+      x + 1,
+      y + (value <= 2048 ? 9 : 10),
+      TILE_SIZE,
+    );
+  };
+
+  for (let row = 0; row < BOARD_SIZE; row += 1) {
+    for (let col = 0; col < BOARD_SIZE; col += 1) {
+      renderTile(col, row);
+    }
+  }
 });
 
-defineOptions({
-  render: () => null,
+const getCell = (row: number, col: number) => board[row]![col]!;
+const setCell = (row: number, col: number, val: number) => {
+  board[row]![col] = val;
+};
+
+const compact = (rowDir: number, colDir: number) => {
+  const reversed = rowDir > 0 || colDir > 0;
+  const start = reversed ? BOARD_SIZE - 1 : 0;
+  const step = reversed ? -1 : 1;
+
+  for (let major = 0; major < BOARD_SIZE; major += 1) {
+    for (let times = 0; times < BOARD_SIZE - 1; times += 1) {
+      for (let minor = start; minor >= 0 && minor < BOARD_SIZE; minor += step) {
+        const row = rowDir !== 0 ? minor : major;
+        const col = colDir !== 0 ? minor : major;
+        const nextRow = row - rowDir;
+        const nextCol = col - colDir;
+
+        if (nextRow < 0 || nextRow >= BOARD_SIZE) continue;
+        if (nextCol < 0 || nextCol >= BOARD_SIZE) continue;
+
+        if (getCell(row, col) === 0 && getCell(nextRow, nextCol) !== 0) {
+          setCell(row, col, getCell(nextRow, nextCol));
+          setCell(nextRow, nextCol, 0);
+        }
+      }
+    }
+  }
+};
+
+const merge = (rowDir: number, colDir: number) => {
+  const reversed = rowDir > 0 || colDir > 0;
+  const start = reversed ? BOARD_SIZE - 1 : 0;
+  const step = reversed ? -1 : 1;
+
+  for (let major = 0; major < BOARD_SIZE; major += 1) {
+    for (let minor = start; minor >= 0 && minor < BOARD_SIZE; minor += step) {
+      const row = rowDir !== 0 ? minor : major;
+      const col = colDir !== 0 ? minor : major;
+      const nextRow = row - rowDir;
+      const nextCol = col - colDir;
+
+      if (nextRow < 0 || nextRow >= BOARD_SIZE) continue;
+      if (nextCol < 0 || nextCol >= BOARD_SIZE) continue;
+
+      if (
+        getCell(row, col) !== 0 &&
+        getCell(row, col) === getCell(nextRow, nextCol)
+      ) {
+        setCell(row, col, getCell(row, col) * 2);
+        setCell(nextRow, nextCol, 0);
+      }
+    }
+  }
+};
+
+const spawnTile = () => {
+  const empty: [number, number][] = [];
+  for (let row = 0; row < BOARD_SIZE; row += 1) {
+    for (let col = 0; col < BOARD_SIZE; col += 1) {
+      if (getCell(row, col) === 0) empty.push([row, col]);
+    }
+  }
+  if (empty.length === 0) return;
+
+  const [row, col] = empty[Math.floor(Math.random() * empty.length)]!;
+  setCell(row, col, Math.random() < 0.9 ? 2 : 4);
+};
+
+const resetBoard = () => {
+  for (let row = 0; row < BOARD_SIZE; row += 1) {
+    for (let col = 0; col < BOARD_SIZE; col += 1) {
+      setCell(row, col, 0);
+    }
+  }
+
+  spawnTile();
+  spawnTile();
+};
+
+const isDead = () => {
+  for (let row = 0; row < BOARD_SIZE; row += 1) {
+    for (let col = 0; col < BOARD_SIZE; col += 1) {
+      if (
+        getCell(row, col) === 0 ||
+        (col < BOARD_SIZE - 1 && getCell(row, col) === getCell(row, col + 1)) ||
+        (row < BOARD_SIZE - 1 && getCell(row, col) === getCell(row + 1, col))
+      )
+        return false;
+    }
+  }
+  return true;
+};
+
+resetBoard();
+
+const slide = (rowDir: number, colDir: number) => {
+  const before = board.map((r) => [...r]);
+
+  compact(rowDir, colDir);
+  merge(rowDir, colDir);
+  compact(rowDir, colDir);
+
+  const moved = board.some((r, i) => r.some((c, j) => c !== before[i]![j]));
+  if (!moved) return;
+
+  spawnTile();
+  if (isDead()) {
+    confirmationModal.open({
+      text: "Game Over!\nRestart?",
+      onConfirm: () => {
+        resetBoard();
+        confirmationModal.close();
+      },
+      onCancel: () => {
+        confirmationModal.close();
+      },
+    });
+  }
+};
+
+useKeyDown((key) => {
+  switch (key) {
+    case "NDS_UP":
+      slide(-1, 0);
+      break;
+    case "NDS_DOWN":
+      slide(1, 0);
+      break;
+    case "NDS_LEFT":
+      slide(0, -1);
+      break;
+    case "NDS_RIGHT":
+      slide(0, 1);
+      break;
+  }
 });
 </script>
+
+<template>
+  <CommonButtons
+    :y-offset="confirmationModal.buttonsYOffset"
+    b-label="Cancel"
+    a-label="Restart"
+    @activate-b="handleActivateB()"
+    @activate-a="handleActivateA()"
+  />
+</template>