To successfully forge items in Adamantine Forge, players must first defeat Grym the Adamantine Golem, a fearsome and practically invulnerable construct. Grym is one of the toughest bosses in Act One, with a significant health pool and an array of immunities and resistances that make it challenging to take down. However, certain tactics can make this fight much easier, even on the tough new Honor Mode difficulty.
Players will encounter Grym at the end of their quest to find and use the Adamantine Forge to craft Adamantine Gear. This quest involves exploring the Grymforge and collecting gear molds and Mithral Ore for the forging process. There are six different Adamantine Forge items; however, due to limited resources, you can only craft two. Grym has to be defeated before you can collect any items.
When fighting Grym, a strong party composition in with multiple companions who are either highly mobile or capable of tanking damage is essential, and ranged weapons are a must-have. Grym is immune to damage unless it has the Superheated debuff, which is applied whenever it's in contact with lava. Have a party member always stand by the Lava Valve, allowing you to flood the area with lava to maintain the debuff. Even with Superheated, Grym is either immune or resistant to all damage types, with a single vulnerability to Bludgeoning damage. This leaves it vulnerable to blunt weapons but also to the Forge Hammer.
The easiest way to defeat Grym in is to lure it to the Crucible platform in the middle before triggering the Forge Hammer by interacting with the Forge Lever. The Forge Hammer will strike the Crucible, dealing immense Bludgeoning damage and knocking Grym Prone. This simple trick makes defeating Grym much easier, and a few strikes from the Forge Hammer will be enough to kill Grym.
Grym automatically targets the last party member who attacked it. Use this to lure Grym over to the Crucible by attacking it.
However, this tactic prevents you from obtaining A Grym Fate,
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