Grim Dawn is an action RPG developed by Crate Entertainment set inside a apocalyptic fantasy world where humanity is on the brink of extinction, iron is valued above gold and trust is hard earned. Grim Dawn features complex character development, hundreds of unique items, crafting and quests with choice & consequence.Read more on Steam
More about the major expansions of Grim Dawn.
The game currently consists mainly of the base game with the expansions Ashes of Malmouth and Forgotten Gods. Only people with the same installed Expansions can play together in online coop mode.
Each expansion brings multiple new areas, items, quests and other in-game content. All of them a storyline of their own but interconnected.
The DLC "The Crucible" is considered to be an addition outside of the main game and mainly used for farming in-game items and materials. It does not affect the ability to play in coop.