Had to fit this in a reply cause video limit.
Just Shapes and Beats:
Closest sibling to this I can come up with is Super Hexagon? I never played Hexagon, but it seems kinda similar. You don't really do anything in this besides try and stay alive by avoiding projectiles and shapes, but the soundtrack is godlike (if you're in to chiptunes and fakebit anyway) and the visuals are pleasantly seizure-inducing. Has 4 player multiplayer for local play, and they want to add online in the future if they can. Not sure I'd play it a ton solo, but with a few people the multiplayer was a hoot. The dev guy also gets major props for acting like a huge jackass and sitting in his booth with aviators on "live coding" his game by flailing at Hacker Typer.