Trianguloid

Says every input is tuned for feel. You can test that in fifteen seconds flat, and it's the correct thing to have obsessed over, because an arena shooter lives entirely in your hands. A few hundred kilobytes with nothing pulled in from outside also means it starts the instant you click, and instant start is a real feature in a browser.

Shapes, an arena, speed. You can trace that line back a very long way, and it survives because geometry stays readable at any size and any framerate. No textures in the way of seeing what wants to kill you. An old shape, cleanly done. I'll always find time for one of these.

Read the description again. It's all build: bytes, input tuning, portability. Barely a word about what you do once you're stood in the arena, and there's your tell. The craft is obviously present and the size discipline is impressive, but a shooter has to give you a reason to keep going and this offers none. Excellent engine. The game still has to be written on top of it

350KB! And it plays better than things a hundred times that size. Every input has been fussed over and you can feel it the second you strafe. No textures anywhere, and it reads as a decision rather than an unfinished job. Restraint like that is rare.