Summoning the Grigoire boss in Diablo 4 is a surprisingly time-consuming endeavour, as you fight your way through Helltides to collect the special Living Steel material required to challenge him. The Galvanic Saint is one of the four bosses that was added in the Season of Blood as a way to target farm unique items, but gathering what you need to fight them is a task in itself.
While you can fight Grigoire on either Nightmare or Torment world tier, he'll only drop Shards of Agony—one of the materials required to summon the endgame Duriel boss—in the latter. With this in mind, it might be in your best interest to wait until you reach Torment world tier to fight Grigoire, just so you're maximising your rewards for time spent. Whatever you choose, here's how to get Living Steel and summon the Grigoire boss in Diablo 4.
Where to find Living Steel
There are a few different ways to get Living Steel in Diablo 4, but your primary method is to open the Tortured Gift chests during Helltide events. To do this, you need to defeat enemies, gather the Aberrant Cinders they drop, then find a chest on the map to spend them on. While only one chest used to drop Living Steel, you can now get a small amount from every Helltide chest you open as well.
So, here are the different ways to get Living Steel:
- Spend 275 Aberrant Cinders to open a Tortured Gift of Living Steel and get five Living Steel
- Open any regular Tortured Gift chest to get one Living Steel
- As of season four, defeating elites has a chance to drop boss materials, including Living Steel
- Also in season four, Whisper caches can additionally reward you with Living Steel
Tortured Gifts of Living Steel are your best best if you want to get a lot of the material. These are marked on the map during the event, so just save up your cinders and then head to the nearest one to cash them in.
How to summon the Grigoire boss
Now you've got your Living Steel, as the item description hints, you'll need to make your way to the Hall of the Penitent dungeon lair in the Dry Steppes. This is pretty easy to find since the icon appears on the map no matter how far you're zoomed out, similar to the capstone dungeon. If you're curious about what unique items Grigoire can drop, be sure to see our Diablo 4 boss loot tables.
Once inside, fight your way to the Chamber of Penitence and dump your Living Steel in the Light-Touched Altar to summon Grigoire and face the boss. This costs:
- Two Living Steel in Nightmare world tier
- Five Living Steel in Torment world tier
The advantage of fighting him in Torment is that you'll get Shards of Agony for summoning Duriel as well as Ancestral gear.
If you want an idea of what to expect fight-wise, he's basically a giant Knight Penitent enemy in terms of his moveset, but with every swing of his mace he fires out a wave of little electric orbs. He'll also call down lightning strikes, summon lightning totems that create an electric maze partway through the fight, and he'll also call in some soldiers to help him.
