by 
It’s legally distinct bullet hell Castlevania! (And it’s $3 on Steam.)
It’s not often you run across a game with a 99% positive rating. I think part of it is the low price, part of it is the many references (floor chicken and the ubiquitous whip, for example), and part of it is the positive feedback loops as you level up your abilities to survive a little longer. And while it does feel exactly like the sort of game you would waste hours on while playing games on Kongregate, $3 isn’t that much money – it’s even less than Devil Daggers – and it is quite a bit of fun (even if it isn’t particularly challenging).