Stack separated into levels with obstacles.
In Obstacle Stack, the player stacks rectangles to reach checkpoints at the top of the window. The width of the stack changes as overhanging parts of placed rectangles are dropped. Obstacles also block the path of the stack. The player must balance manipulating the shape of the stack to bypass obstacles and maintaining a manageable stack width in order to reach the checkpoint.
Each level starts with a ground. At the start of the game, the ground will be placed beforehand. At subsequent levels, the ground
is a wide rectangle placed by the player upon reaching the checkpoint.
The game maintains the basic rules of Stack. A rectangle will hover back and forth over the existing stack (or the ground at the start). The player must press a key to lock the rectangle's position on the stack. Any overhang over the existing stack will be dropped, reducing the width of the resulting stack. Subsequent rectangles must land on this width. Rectangle width will reduce in proportion to the width of the stack, with some leeway. The player loses if the player fails to place a rectangle over the stack.
Unlike Stack, Obstacle Stack will have obstacles blocking the progress of the stack. The player must manipulate the width and shape of the stack to bypass these obstacles to reach checkpoints. The player loses if the player places a rectangle such that the resulting stack overlaps an obstacle. At each checkpoint, the player places a wide rectangle that serves as a new ground
for the next level. The window then pans up to reveal the next level.
The player wins the level if the player reaches the checkpoint without:
Like Stack, rectangles in the stack should form a pastel-blue gradient that resets at every checkpoint. Obstacles will be denoted by semi-transparent red. Rectangles that are hovering render at half opacity, then become solid when placed. Rectangle parts that are sheared off will fall to the side and fade away. Game elements are displayed in a flat side view.
Below are 64x64 color tiles for blocks.
Below are additional tiles for obstacles and checkpoints (64x64), as well as a dotted line (256x64).
