I didn’t really understand this game when it was explained to me. But I played it once and got it instantly. Now I’m fairly hooked — just detonate an explosion and let its ripples trigger other explosions. Now do it in time with a beat for a bonus multiplier. Then speed up the beat and add more enemies. Throw in your own music, let the game analyze it, and play to that. Oh, and try to get your score in the trillions. I never played the PSP version, so trying the 360 edition was a totally fresh experience.
I also like the minimalist-yet-bonkers visual approach. I happen to like abstract games quite a bit. I think that when you strip out the traditional visual elements that a gamer expects, you’re left with something pure and primal. It’s why I like Tempest and Geometry Wars — they both tell their own abstract tales, and they speak very clearly and directly, with no extraneous information. Yet they still give you something to interpret and decipher on your own. E4 gives me the same vibe.