When you reach the Ancient Forge in Baldur's Gate 3, you're faced with a tough choice: is tracking down the Mithral Ore and defeating Nere or the Guardian worth the grind, or should you skip it and move on? The short answer is yes—the Adamantine Forge yields some of the absolute best Act 1 gear in the game, items you can easily carry well into Act 2 and even early Act 3.
However, the effort involves navigating the treacherous Grymforge, managing limited Mithral deposits, and surviving a punishing boss fight against Grym. If you're short on time or struggling with tactical combat, figuring out whether the trip pays off depends on your party composition and build strategy. Let's break down the actual costs, rewards, and hidden optimization tricks so you can decide if it's worth your time.
Understanding the Adamantine Forge Rewards
You can only craft two items per playthrough because the Underdark only contains two chunks of Mithral Ore. With six total weapon and armor options to choose from, making the right selection dictates your return on investment.
The Armor Pieces
The heavy and medium armor options are widely considered the standout rewards from the forge because of their unique passive traits.
- Adamantine Splint Armor (Heavy): Grants 18 AC and the Splint Armour feature, which reduces all incoming damage by 2. Crucially, attackers cannot land critical hits on you, and anyone who hits you in melee combat is afflicted with Reeling for two turns, imposing a -1 penalty to their attack rolls per turn.
- Adamantine Scale Mail (Medium): Grants 16 AC, reduces incoming physical damage by 1, prevents critical hits, and inflicts Reeling on melee attackers. This armor is exceptionally strong for medium armor wearers like Shadowheart, Minthara, or Lae'zel if you aren't running heavy armor.
The Weapons and Shields
While the armor pieces offer passive defense that scales brilliantly into higher difficulties, the weapon options are more situational.
- Adamantine Longsword and Scimitar: Both weapons bypass resistance to slashing damage and ignore objects' resistance and immunity. They also automatically score a critical hit when striking objects, making them great utility weapons for smashing sturdy doors, chests, and barriers.
- Adamantine Shield: Grants +2 AC, prevents critical hits, knocks attackers prone when they miss a melee attack against you (provided you pass a saving throw check), and offers a tactical edge in crowded frontline engagements.
The True Cost of Crafting
Getting to the forge isn't a quick walk in the park. You have to commit substantial resources and time to the process.
First, you need to explore the entire Grymforge zone, clear out or bypass the Duergar faction, and rescue Nere (or loot his corpse). Next, you have to mine two veins of Mithral Ore, which are guarded by animated armors and lava pools. Finally, you have to collect matching weapon moulds or armor moulds scattered around the upper and lower levels of the Adamantine Forge complex.
The biggest resource cost isn't gold—it's action economy and spell slots during the boss encounter. Grym hits like a freight train, and if you aren't prepared with blunt weapons or positioning tricks, you'll burn through all your healing potions and revivify scrolls.
How to Beat Grym Efficiently
The main barrier stopping players from getting their gear is the guardian boss, Grym. If you fight him blindly, the battle drags on and drains your resources. You can cheese or optimize the fight easily by following a few concrete steps:
- Bring Bludgeoning Weapons: Grym has immunity to almost all damage types except bludgeoning. Equip your fighters and barbarians with warhammers, maces, or clubs before pulling the lava valve.
- Control the Temperature: Keep Grym Superheated by ensuring he stands in the lava channels. When he's superheated, his immunity to bludgeoning damage drops away.
- Use the Hammer Anvil: Instead of chipping away at his health bar with normal attacks, position a tank near the central crucible and pull the lever to drop the giant hammer on him for massive chunk damage.
- Mind the Positioning: Use ranged characters or summoned mage hands to manipulate the valves and levers from safety, keeping your heavy hitters in position to bait Grym onto the stamp.
Common Mistakes to Avoid
Many players lock themselves out of optimal gear or waste precious materials due to a few common oversights.
- Wasting Mithral on Weapons First: The weapons lose their competitive edge by the time you reach Act 2, whereas the armor's anti-critical hit trait remains useful well into Act 3. Craft at least one piece of armor unless your build specifically requires a dual-wielding or two-handed weapon strategy.
- Leaving Moulds Behind: It's easy to miss the scale mail mould or the shield mould on the upper scaffolding before descending to the lava chamber. Double-check your inventory and exploration path before activating the forge.
- Forgetting to Loot the Boss: After defeating Grym, make sure to loot the Grym Helm from his core remains. It grants Deafening Immunity and a reaction attack bonus, completing your heavy armor set.
Frequently Asked Questions
Can I get more than two items from the Adamantine Forge?
No. There are only two veins of Mithral Ore available in the entire game world. Once you use both pieces, the forge cannot be activated again, so choose your two items carefully.
What happens if I lose a mould inside the lava?
Moulds don't get destroyed by lava. If you accidentally drop a mould or leave it on the platform, you can pick it back up as long as you clear the area or wait out the environmental hazards.
Is the Adamantine Splint Armor better than magical Act 2 armor?
Yes, for certain builds. The ability to negate critical hits entirely and apply Reeling to enemies makes the defensive mitigation superior to many higher-rarity armors you find early in Act 2.
Do I need to fight Grym to use the forge?
Technically, no player has found a reliable way to bypass Grym entirely without mods. You must engage the boss to lower the platform and activate the crucible safely. Check out official guides on Larian Studios for community-voted patch notes and mechanics updates.
