Kromaia is weird, but it's the most successful game at creating one of the feelings I've always wanted out of gaming: the sensation of diving into utter madness.
It's a 3rd-person 6-degrees-of-freedom shooter taking place in a vaguely Tron, vaguely Mayan world where you are tasked with collecting a series of 20 macguffins scattered throughout an obstacle course of ruins then defeating a giant boss monster, all the way fighting off increasingly dense swarms of enemies with flocking behavior and adaptive AI. The interesting twist is that (most) enemies zoom in front of you before they start shooting, giving the whole thing the feeling of a rail shooter like Starfox.
Rez is the most cited comparison for this game's aesthetic, but to me it just feels like an overgrown Atari 800 game (in a good way).
The main negative is the odd mouselook controls. For the most part it moves consistently, though limited in maximum turn speed by the ship's own physics. However for some strange reasons doing a tiny mouse movement causes the ship to suddenly spin at great speed, faster than if you were moving the mouse quickly. It's weird, but you get used to it.