Okay DLC with only one add-on.
Grim Dawn is a great game and a satisfying RPG that plays very straightforward and easy. Like other RPG's, you control a character, defeat monsters and bosses, level up, spend skill points and complete quests. It is as classic as it will ever be. Grim Dawn has some unique features, however.
In Grim Dawn, you play as a character that has been possessed by the Aetherials and cured by the survivors of Devils Crossing. You start your adventure and fight against the forces of the dead, demons and other vile beasts. Like any classic RPG, your goal is to save the world and be the ultimate hero of the realms.
At any time, you can access the DLC's, including this one, Grim Dawn: Crucible. In Grim Dawn: Crucible, you can enter a special arena, full of challenges and deadly monsters for great rewards.
This DLC only adds the new arena feature. For 7 euro's, I think that is quite expensive.
This is one of those games that you need to keep playing for years and years to fully complete. Not necessarily because of the endless content, but rather because of the inhumane grind for levels, renown status and special items with low drop rates.
I would surely recommend this DLC to complete your experience with Grim Dawn.