Thiollier, added to Elden Ring in the Shadow of the Erdtree DLC, has quite a long and involved questline. This requires a lot of work and spans most of the timeline covered by the DLC, so don’t worry about rushing through it. You do want to complete the below steps before getting to Enir-IIlim, but that appears to be the only time gating.
Thiollier’s Questline in Elden Ring
Step 1 – FInding Thiollier at the Pillar Path Cross
The first thing to do is actually find Thiollier. He is located at the Pillar Path Cross, which is southeast of Castle Ensis. Talk to him
Step 2 – Go and Talk to Moore
You can find Moore at the Castle Gate Cross, where you can talk to him. As long as you have already spoken to Thiollier, he will give you an item for him called Black Syrup. Moore is something of a wheeler and dealer, and he is always tasked with tracking things down for other NPCs.
Step 3 – Back to Thiollier at the Pillar Path Cross
Return to Thiollier and give him the Black Syrup. He will be quite grateful and praise Moore’s ability to find obscure things. Now, after you give him the black syrup, make sure you ask him about it, then select the dialogue option “I am tired of life.” He will give you a Concoction if you do this.
Step 4 – Continue to play through the game
Continue to explore the game until you break the charm that Miquella has cast on everyone. You will get a message on screen when this happens, and it should occur as you get close to the Shadow Keep or some other areas. When you get “somewhere, a great rune has broken, and so too has a powerful charm” appearing on your screen, it is time to head back to Pillar Path Cross and talk to Thiollier yet again. He will advise you that he plans to go south. He will talk about St. Trina (a familiar character from the main game).
Step 5 – Heading south to the Cerulean Coast
You will need to keep heading southeast from where you find Thiollier, and you will find the Dragon’s Pit. It’s a dangerous place, with some fun fights, and you need to get through it all to come out the other side in the Jagged Peaks. Once you are there, you’ll find all manner of scary fights, but you can also just head south toward the Dragon Communion Altar, and then keep going south from there to get to the Cerulean Coast.
Step 6 – Down into the Fissure
Now it’s time to dive down into the Stone Coffin Fissure. Anyone who was here before breaking the great rune will have been unable to enter, but it will be accessible now as Miquella no longer has the power to seal it off. You can enter by jumping from ledge to ledge down the south side. Just take it slowly so you don’t fall to your death. Once you get down into the Fissure itself, it is a pretty straightforward journey with only one main route forward.
There are a lot of enemies in this place. Big guys with clubs, the armored birds that I really hate, skeletons that come back together if you don’t smash them after they break apart, and more worms than you’ve ever seen in your life. Be patient and make your forward, following the logical path as you go.
Eventually, you will come to a strange Site of Grace with lots of animals gathered around. Walk up the nearby steps and jump off the statue head to arrive in a very pretty but dangerous place. You will drop down into a large area where you will have the option to summon Thiollier. I have been unable to figure out yet if you need to summon him for his quest, but I did it just to be safe. You will now need to fight the Purtrescent Knight, a powerful enemy that will likely give you fits. Think Orphan of Kos on a horse, for some reason, and you are in the right ballpark. When you take him out, move forward and grab the new Site of Grace. This place is called the Garden of Deep Purple.
Step 7 – Onward to Thiollier
Walk down the tunnel with the purple glow, and you will find Thiollier. He is not having his best moment and is somewhat overcome by being in the presence of St. Trina. He has been drinking some of her poison and claims he is about to pass into a deep sleep. He also says this poison is just for him, and you can’t have any—greedy fella. Reload back into the area again, and make sure you fully exhaust all his dialogue options both times.
Step 8 – Nectar time
Now, you need to interact with St. Trina and take the option to imbibe the nectar. You will need to drink a lot of it and take it up to four times. Each time you do, you will die, but that’s not a problem for the Tarnished! Just head back each time and drink again. The second time you come back, Thiollier will be begging St. Trina for more poison and tell you to let him be. When you drink for the fourth time, St. Trina will speak to you, asking you not to let poor Miquella turn into a god.
Tell this to Thiollier, who will get a bit miffed because you heard the voice of St. Trina before him. He won’t really believe you, so tell him again, and he will get really angry with you.
Step 9 – Thiollier gets mad
Thiollier really didn’t like the fact that you got to speak to St. Trina, but he did not. He decides it’s time to throw hands, which is a big move for a lad who was just crying in a cave. As he said himself, he isn’t much of a scrapper, but he does have some interesting poison attacks. Simple dodge rolling gets the job done, and you can deal with him easily enough. It does put a bit of manners on him, however, and he goes back to his crying spot in the cave again.
Step 10 – Pass on the words to Thiollier
Go back into the cave and talk to Thiollier once again. You will find him a bit more receptive to things this time. You won’t get a dialogue option though, and will need to imbibe the nectar twice more to get more dialogue from St. Trina. She will tell you that godhood isn’t really it for Miquella and will be more of a prison than anything else. She will then ask you to kill him and grant him forgiveness.
Talk to Thiollier again, pass on the message, and do your best to ignore how surely he is. From that point on, you’ll only be able to hear him snore, and there is little point in drinking more nectar.
Huge Spoilers Ahead
You can now summon Thiollier for two important fights.
- Against Leda and her goons at Enir-IIim. This fight is pretty wild and involves a lot of NPCs who are figuring out their stance on Miquella.
- In the very last boss fight, you will be able to summon Thiollier to help in the final boss fight, and doing so will give you the chance to loot him for his Hidden Needle and armor.
- You can then return to St. Trina for a little bit of a wrap-up.
