diff --git a/src/bin/tetris.rs b/src/bin/tetris.rs
index e897d2c..987ca2e 100644
--- a/src/bin/tetris.rs
+++ b/src/bin/tetris.rs
@@ -13,28 +13,6 @@ struct Position {
     pub z: u32, // render order
 }
 
-impl Add for Position {
-    type Output = Self;
-    fn add(self, other: Self) -> Self {
-        Self {
-            x: self.x + other.x,
-            y: self.y + other.y,
-            z: self.z + other.z,
-        }
-    }
-}
-
-impl Sub for Position {
-    type Output = Self;
-    fn sub(self, other: Self) -> Self {
-        Self {
-            x: self.x.saturating_sub(other.x),
-            y: self.y.saturating_sub(other.y),
-            z: self.z.saturating_sub(other.z),
-        }
-    }
-}
-
 #[derive(Component, Debug, Reflect)]
 struct Size {
     width: f32,
@@ -50,17 +28,6 @@ impl Size {
     }
 }
 
-fn spawn_tile(commands: &mut Commands, color: Color, size: f32, position: Position) -> Entity {
-    commands
-        .spawn(Sprite {
-            color,
-            ..Default::default()
-        })
-        .insert(position)
-        .insert(Size::square(size))
-        .id()
-}
-
 fn post_scale_tiles(
     window: Single<&Window>,
     matrix: Res<Matrix>,
@@ -75,28 +42,6 @@ fn post_scale_tiles(
     }
 }
 
-fn post_translate_tetrominos(
-    window: Single<&Window>,
-    matrix: Res<Matrix>,
-    mut q: Query<(&Position, &mut Transform), With<Tile>>,
-) {
-    // We subtract half the window width because our coordinate system starts at the bottom left, and
-    // Translation starts from the center. We then add half the size of a single tile, because we want
-    // our sprites bottom left corner to be at the bottom left of a tile, not the center.
-    fn convert(pos: f32, bound_window: f32, bound_game: f32) -> f32 {
-        let tile_size = bound_window / bound_game;
-        pos / bound_game * bound_window - (bound_window / 2.) + (tile_size / 2.)
-    }
-
-    for (pos, mut transform) in q.iter_mut() {
-        transform.translation = Vec3::new(
-            convert(pos.x as f32, window.width(), matrix.width as f32),
-            convert(pos.y as f32, window.height(), matrix.height as f32),
-            pos.z as f32,
-        );
-    }
-}
-
 fn post_translate_tiles(
     window: Single<&Window>,
     matrix: Res<Matrix>,
@@ -119,16 +64,29 @@ fn post_translate_tiles(
     }
 }
 
-#[derive(Component, Debug)]
-struct TetrominoCoords([[u32; 2]; 4]);
+fn translate_tetrominos(
+    tetrominos: Query<(&Tetromino, &mut Children)>,
+    mut positions: Query<&mut Position, With<Tile>>,
+) {
+    for (t, children) in tetrominos.iter() {
+        for child in children.iter() {
+            let mut p = positions.get_mut(*child).unwrap();
+            p.x += t.pos.x;
+            p.y += t.pos.y;
+        }
+    }
+}
 
-const BRICK_I: TetrominoCoords = TetrominoCoords([[0, 0], [1, 0], [2, 0], [3, 0]]);
-const BRICK_J: TetrominoCoords = TetrominoCoords([[0, 0], [1, 0], [2, 0], [2, 1]]);
-const BRICK_L: TetrominoCoords = TetrominoCoords([[0, 0], [1, 0], [2, 0], [0, 1]]);
-const BRICK_O: TetrominoCoords = TetrominoCoords([[0, 0], [1, 0], [0, 1], [1, 1]]);
-const BRICK_S: TetrominoCoords = TetrominoCoords([[0, 0], [1, 0], [1, 1], [2, 1]]);
-const BRICK_T: TetrominoCoords = TetrominoCoords([[0, 0], [1, 0], [2, 0], [1, 1]]);
-const BRICK_Z: TetrominoCoords = TetrominoCoords([[0, 1], [1, 1], [1, 0], [2, 0]]);
+#[derive(Component, Debug, Clone, Reflect)]
+struct TetrominoKind([[u32; 2]; 4]);
+
+const BRICK_I: TetrominoKind = TetrominoKind([[0, 0], [1, 0], [2, 0], [3, 0]]);
+const BRICK_J: TetrominoKind = TetrominoKind([[0, 0], [1, 0], [2, 0], [2, 1]]);
+const BRICK_L: TetrominoKind = TetrominoKind([[0, 0], [1, 0], [2, 0], [0, 1]]);
+const BRICK_O: TetrominoKind = TetrominoKind([[0, 0], [1, 0], [0, 1], [1, 1]]);
+const BRICK_S: TetrominoKind = TetrominoKind([[0, 0], [1, 0], [1, 1], [2, 1]]);
+const BRICK_T: TetrominoKind = TetrominoKind([[0, 0], [1, 0], [2, 0], [1, 1]]);
+const BRICK_Z: TetrominoKind = TetrominoKind([[0, 1], [1, 1], [1, 0], [2, 0]]);
 
 enum RenderLayer {
     Background = 0,
@@ -146,21 +104,47 @@ struct TileBundle {
     tile: Tile,
 }
 
-fn spawn_tetromino(commands: &mut Commands, tetromino: TetrominoCoords, x: u32, y: u32) {
-    for coord in tetromino.0 {
-        commands.spawn(TileBundle {
-            position: Position {
-                x: coord[0] + x,
-                y: coord[1] + y,
-                z: RenderLayer::Brick as u32,
-            },
-            size: Size::square(0.77),
+fn spawn_tile(commands: &mut Commands, color: Color, size: f32, position: Position) -> Entity {
+    commands
+        .spawn(TileBundle {
+            position,
+            size: Size::square(size),
             sprite: Sprite {
-                color: Color::srgb(0.8, 1.0, 0.8),
+                color,
                 ..Default::default()
             },
             tile: Tile,
-        });
+        })
+        .id()
+}
+
+#[derive(Component, Reflect)]
+struct Tetromino {
+    pos: Position,
+    kind: TetrominoKind,
+}
+
+fn spawn_tetromino(commands: &mut Commands, kind: TetrominoKind, x: u32, y: u32) {
+    let tetromino = commands
+        .spawn(Tetromino {
+            pos: Position { x, y, z: 0 },
+            kind: kind.clone(),
+        })
+        .insert((Transform::default(), Visibility::default()))
+        .id();
+
+    for coord in kind.0 {
+        let e = spawn_tile(
+            commands,
+            Color::srgb(0.3, 0.3, 0.8),
+            0.9,
+            Position {
+                x: x + coord[0],
+                y: y + coord[1],
+                z: RenderLayer::Brick as u32,
+            },
+        );
+        commands.entity(e).set_parent(tetromino);
     }
 }
 
@@ -178,11 +162,15 @@ fn main() {
         Startup,
         (init_singletons, init_window, init_tile_grid).chain(),
     )
-    .add_systems(PostUpdate, (post_scale_tiles, post_translate_tiles));
+    .add_systems(
+        PostUpdate,
+        (translate_tetrominos, post_scale_tiles, post_translate_tiles).chain(),
+    );
 
     app.add_plugins(debug_plugin::debug_plugin);
 
     app.register_type::<Position>();
+    app.register_type::<Tetromino>();
     app.register_type::<Size>();
 
     // Run the app