Voidbreaker
Vertical arcade shooter. Five stages, five bosses, endless mode.
PlayNo games match that — try clearing the search.
Tabbreak is a small collection of games that run in a browser tab. No downloads, no account, no launcher. Every game is built to start in under three seconds on a slow connection, which means they work on school Chromebooks and old phones — the hardware most game sites quietly stop supporting.
New games are added a few at a time rather than by the hundred. A page here has one game on it and something worth reading about that game.