Black Hole Square Unblocked

Black Hole Square was built for js13k 2021, a contest where the whole game had to squeeze into 13 kilobytes, and it shows in the best way. There is a 6x6 board, some white tiles, a few black holes and a move counter, and that is it. Nobody explains the rules. You learn what each tile does by tapping it and watching. This unblocked copy runs right in your browser, and since every action is a tap or a sideways swipe, it plays comfortably on a phone held in one hand.

The Tiles and What They Do

The puzzle name sits in the top left of each board, with your remaining moves in the top right.

• Arrow tiles are the only real movers. Tap one and it shoves itself, plus every tile lined up ahead of it, one cell in the arrow’s direction. If the line ends at an empty cell, the whole row shifts. If it ends at a black hole, the front tile drops in and vanishes. If it hits the edge of the board, nothing happens and you keep your move.
• Plain white tiles cannot be tapped. They only travel when an arrow pushes them.
• X tiles disappear the moment you tap them.
• Neutron stars, the tiles with a gray square in the middle, collapse into a brand-new black hole when tapped.

A board is solved when only black holes are left. If you run out of moves, get stuck, or strand plain tiles, the game tells you why and slides the same board back in for another try.

Black Hole Square controls

To do this	Mouse	Touch
Tap a tile to push, pop or collapse it	Click the tile	Tap the tile
Move on to the next screen	Drag left across the board, or scroll sideways on a trackpad	Swipe left
Restart the puzzle, or step back if you have not moved	Drag right across the board, or scroll sideways on a trackpad	Swipe right
Pick any puzzle from the list	Click a square in the progress row under the board	Tap a square in the progress row under the board

How to Stop Wasting Taps

Most failures come from tapping too soon. Before touching anything, count the tiles that must leave the board and compare that with the move budget. The very first board gives you exactly four taps for four jobs, and that tightness never goes away.

Line things up, then push once. Because an arrow drives everything in front of it, three tiles in a row can be marched toward a hole with far fewer taps than three separate trips.

Guard the plain tiles. A white tile with no arrow behind it, in any direction, can never leave. Before you move an arrow away, make sure it is not the only thing that can reach a plain tile.

Think of neutron stars as hole placement. Collapsing a star early can put a target right in the path of a row you were going to push anyway.

Do not always pop an X. Tapping an X costs a move. If an arrow is already shoving that row into a hole, the X can ride along for free.

When a board feels impossible, swipe right to reset and replay it slowly. The solutions are usually short once you spot the order.

Who Will Like It

Black Hole Square is ideal for a five-minute break, since each board is small and resets instantly. It rewards the same kind of planning as Tower of Hanoi, where every move must earn its place. For more compact brain teasers, browse the full puzzle games list.