viperfdl: I'll try:
The level are randomly generated in which rooms are connected with corridors, like e.g. in Ziggurat. Between levels you decide in this diagram - see last screenshot on the game page - where to go next. Both things put me off. There are barrier that damage you when you destroy them and behind some of them are secrets. Health pickups fill a meter that when full can be used to replenish your health but not to the max. And that health pickups are rather dropped seldom.
You start your first runs only with a sword and have to find guns in the levels but you can unlock guns in the upgrade tree later. You seem to only be able to carry three weapons at once.