Testament

From BoardGameGeek:

Testament is a cooperative monster battle card game from Manifest Destiny and LionWing Publishing modeled after the typical "MMORPG trinity" of tank, healer, and damage dealer. The players control four characters and choose which skills each character should have. Each turn, new mob cards are drawn, and the players must defeat these by effective use of their various skills, all the while managing mana, aggro, and various threats. The game consists of six stages, each stage ending with a boss fight, which follow specific rules. Each stage has a playtime of about an hour. The game can start at any stage or be played as a campaign, with characters leveling up after each stage. The difficulty setting is hard, with the designer claiming that few stand a real chance on their first playthrough.