Riposte

A sharp one-thumb arcade game: you are the glowing core, and every tap fires a single expanding pulse ring. Time the ring's radius to shatter incoming shards — let bulwarks drift deep before the ring is strong enough, snap streaks while they're still close, or wait for one big ring to clear a whole cluster. Chained kills build a combo multiplier; letting a shard reach your core costs a charge. Survive the escalating spawn waves.