Wipe 'em Out!

From BoardGameGeek:

In this fast-paced game, players are adventurers entering a cave full of monsters, using artifacts and magic to defeat as many of them as possible. Each round, each player chooses an artifact to use, and can take turns playing magics to improve their artifacts or make their opponents' artifacts worse. At the end of the round, the player with the best artifact wins the monster currently in the cave, and each player chooses to complete their hand of cards or change their hand of cards completely. A new monster is revealed and a number of rounds dependent on the number of players are held. At the end of the game, each type of monster scores in a different way and whoever has the most points wins.