Got this as a random in the Humble Freedom Bundle. Run and gun Serious Sam style in a procedurally generated tunnel maze. Variety of guns and powerups you can unlock, but really it's a game for killing a little time in quick runs, there's no larger story or campaign. It's probably not worth the $15 full freight, but if it went on sale for $10 or less and you like that kind of gameplay, it would be worth looking at.
The middle school gang played this for one or two marathon sessions and were done with it.
Why am I homeless? Why do all you motherfuckers need homes is the real question. They called it The Prayer, its answer was law Mommy come back 'cause the water's all gone