99 Levels to Hell

99 Levels to Hell is a 2D roguelike platform shooter consisting of ten randomly created ten-level dungeons. To make it out of each level, you must survive long enough to find the key and the door it unlocks, avoiding traps and blasting all the monsters that try to stop you. To move from one dungeon to the next, you must defeat the boss on its tenth level.

On top of gold, guns, upgrades and magic, the dungeons also hide shops, casinos, portals, elevators that randomly transport you to another level, secret rooms that unlock more of the story and even new adventurers which may be selected in the next game once freed. Death is permanent, however, making you lose everything you had and restart from the first level of the dungeon you were in when it occurred. If there's any silver lining to that, it's that it allows you to start using a newly found weapon, seeing as doing so otherwise requires you to give up on all the upgrades found for the one you had been using until then.