Throne of Agony is the sequel to Dungeon Siege II and it picks up the story where the previous game and its add-on left off; after the 2nd cataclysm altered the world of Aranna. Along with the familiar hack 'n slash dungeon crawling gameplay, it also has new playable characters and a non-linear, single player campaign, and co-operative multi-player. There are two different game modes: Normal and Elite. Player can choose from multiple characters, which are customized as they level up into Hero classes and Legendary classes.
There are numerous pets and companions to play with. Gameplay involves switching between unique pets and companions to use their special powers. Face over 100 monsters (some from the Dungeon Siege world as well as many new creatures).
Cooperative campaign allows you to play with a friend where each player can bring a pet or companion. The game also has multi-player "Battle Arenas" for players who don't have time for a full campaign.