The game barely explains itself, and that is the point. You get a small grid, a few white tiles, some black holes and a move counter. Working out what each tile does when you tap it is the first puzzle, and using that knowledge with no spare moves is the rest.
Black Hole Square unblocked was made for the js13k 2021 contest, so the whole game fits in 13 kilobytes. There are 18 puzzles, and your solved ones are remembered in your browser.
How to play Black Hole Square
Swipe left past the opening screens to reach the first board. The puzzle's name is in the upper left, and the moves you still have are in the upper right. Only a tap that changes the board uses a move.
An arrow tile pushes itself and every tile in a line ahead of it one square in the arrow's direction. If the front tile is next to a black hole, it falls in and is gone. If the line is pressed against the edge, nothing happens. Plain tiles can't be tapped and only move when pushed.
A tile with an X disappears when you tap it. A tile with a gray center is a neutron star, and tapping it collapses it into a brand new black hole. The goal is a board with nothing left but black holes. Running out of moves or getting stuck sends the same puzzle back to its start.
Controls
| To… | Mouse | Touch |
|---|---|---|
| Tap a tile (push a row, pop an X, or collapse a star) | Click the tile | Tap the tile |
| Skip to the next screen | Drag left across the board, or scroll sideways on a trackpad | Swipe left |
| Reset the puzzle (or go back if no moves were made) | Drag right across the board, or scroll sideways on a trackpad | Swipe right |
| Jump to any puzzle | Click a square in the progress row under the board | Tap a square in the progress row under the board |
Tips
- Plan the whole solution before tapping. The move count is usually exact, so look for a sequence that uses every tap.
- Make lines before you push. One arrow can carry several tiles at once, so arrange a row first and clear them together.
- Never strand a plain tile. It can only leave by being pushed, so keep it in some arrow's path.
- Place new holes with care. A collapsed neutron star becomes a target, so collapse it where a row is already heading.
- X tiles can ride a push too. Shoving one into a hole saves the tap you would spend removing it.
Black Hole Square questions
How do I restart a puzzle?
Swipe right. That resets the current board, or takes you back a screen if you haven't made a move yet.
Does the game save my progress?
Yes. Your current puzzle and the ones you have solved are kept in your browser, and the progress row shows them when you come back.
Does it work on a phone?
Yes. It is built around taps and sideways swipes, and the grid resizes for an upright screen, so one hand is enough.
Can I skip a puzzle I'm stuck on?
The game lets you jump to any puzzle, so you can try a different board and come back later with fresh eyes.
