FuseBlast fills a 5×5 grid with numbered blocks, each showing a countdown from three to nine. Every second the entire grid ticks down by one automatically. When any block reaches zero it explodes, dealing one point of damage to each of its four neighbours. If those neighbours also hit zero they explode in turn. If five or more blocks detonate in a single second the grid is overwhelmed and the game ends. Your only tool is a limited supply of fuses — tap any block to add two to its countdown and buy it more time. You start with twenty fuses and earn one more every ten seconds you survive. The lowest countdown blocks are coloured bright red as a warning — keep an eye on them and triage before they trigger a chain. The longer you survive the higher your score, which rewards both time alive and fuses remaining. There is no way to win — only to last as long as possible.