About iptsi Merge
iptsi Merge is a sliding tile puzzle played on a four-by-four board. Every swipe moves all the tiles as far as they will go in that direction. When two tiles carrying the same number meet, they combine into a single tile worth double, and a new tile appears in an empty space. The run ends when the board is full and no two neighbours match.
There is no timer, which changes the kind of attention the game asks for. Nothing punishes deliberation, so the difficulty is entirely in the long-term consequence of each move: the board fills up because of decisions made twenty swipes earlier, not because of a mistake made just now. That makes it the slowest and most strategic of the games here.
How to play
- Swipe in any direction, or use the arrow keys, to slide the whole board.
- Tiles with the same number merge into one tile worth twice as much, and the merged value is added to your score.
- Only one merge can happen per tile per move, so a row of four equal tiles becomes two doubled tiles, not one quadrupled one.
- The board is full when there are sixteen tiles and no two adjacent tiles match — at that point the run ends.
How it was built
The board is a flat array of sixteen numbers, and each move is a small transform over four lines. It is drawn on a single canvas with rounded rectangles and colour-coded values, so the whole game is one HTML file with no images and no dependencies.
The merge rules are written so that a move never silently does nothing: if a swipe cannot change the board, no new tile is added and no move is counted. That sounds obvious, and it is the single most common way this kind of puzzle feels broken when it is implemented carelessly.
Why it is free
iptsi builds these games ourselves and owns the code and the artwork outright, so there is nothing to license and nothing to attribute. These titles are here to be played, and to demonstrate what works in the open web: instant, offline, and readable on a small screen. There is no account, no download, and no advertising on this page, and your best score stays in your browser.