Dungeon crawls need not be complicated. Card Capture uses simple mechanics to create a thematic fight without the thematic complications. Its small layout also means less space needed to play it and fewer tabs to keep track of.
The layout consist of a draw pile representing the enemies, queued up four at a time at most. At the end of the line is the enemy's discard pile and the goal is to survive through waves of enemies without letting an ace, king, queen or jack reach it.
Your starting arsenal is pretty weak, luckily your method of attack involves capturing cards that you can also use for further attacking. Cards of a suit can capture an equal or lower card of another suit, and jokers take on the same value as another card in your hand.
After the enemies fill their positions, you draw until your hand has four cards (after choosing to discard some or none) and either capture one card, let one card of yours be captured (discarding it and the rightmost enemy card to the enemy) or sacrifice two cards to bring any card on the line to the bottom of the enemy draw pile. Aces, kings, queen and jacks cannot be sacrificed as a consequence.
Going well with the theme, the game starts with your small force matching horribly against the enemies, in some cases forcing you to choose which of your cards will have to perish. You would prefer not to lack too much of a specific suit or you'll find yourself swamped on one front that you cannot fight in any way. Jokers are powerful; it's ability of doubling the amount of a card in your hand should not be underestimated, though you might have to rely on it more often than you want.
Once you manage to gather enough cards the rest of the game is just a matter of having enough right cards at the right time; the only thing stopping you from being OP is having four cards. Any damages taken at this point may get risky and can even cost you the game. A good sense of managing losses will go a long way.
A simple game with an adventurous sense of progress, a rougelike with a deck of cards, Card Capture will do more than that, and if you're done with your adventure, just shuffle yourself another one.