Radical Spectrum is a classically-inspired arcade game with infinitely increasing speed and difficulty, featuring a unique color-collecting mechanic that adds a light puzzle element.
It will require you to focus your attention on multiple things at once, as the bottom of the screen becomes an ever-changing and increasingly difficult bullet-hell landscape, while the ultimate goal keeps flying around the top of the screen. And don't forget about the deadly black radiation coursing through the grid. One drop of that and the whole place is toast.