Contagion Clash is a free online arcade puzzle game where you tap microbes in the correct sequence to trigger chain-reaction shots that eliminate every non-shooting microbe on the screen. The play area fills up with a mix of shooter and passive microbes, and your job is to figure out which ones to activate first so their projectiles clear the rest. Get the order wrong and the chain breaks — simple concept, surprisingly tricky execution. Each level ramps up the complexity, adding more microbes, tighter layouts, and less obvious firing paths. The real satisfaction comes from spotting that perfect sequence and watching the whole board clear in one clean chain. There's no timer breathing down your neck, so you can study the layout, plan your taps, and retry as many times as you need. That said, the puzzles get genuinely challenging, rewarding players who think a few steps ahead rather than just tapping randomly. Contagion Clash is a great pick for fans of chain reaction games, logic puzzles, and casual arcade challenges. If you enjoy tap-to-solve puzzles, microbe-themed strategy games, or free browser puzzle games with no download required, this one delivers tight, satisfying gameplay in short sessions. It fits perfectly for players searching for free online puzzle arcade games, chain reaction strategy games, or petri dish puzzle games to play in the browser.