How To Complete St. Trina Questline (Thiollier Quest) in Elden Ring Shadow of the Erdtree

After the base game teased St. Trina’s existence, Elden Ring: Shadow of the Erdtree is finally gracing its players with her appearance. She’s one of the NPCs in the game and has a rather elaborate side quest tied to her and another NPC named Thiollier. As usual, it’s easy to mess up the St. Trina and Thiollier questline in Elden Ring: Shadow of the Erdtree, so I’ve made a guide to help you piece it all together.

Important Note: DO NOT BURN the Sealing Tree Yet

So what happens if you’ve already burned the Sealing Tree (after defeating Messmer the Impaler)? You’ll get locked out of the St. Trina and Thiollier questline. That depends on what stage you’ve progressed in the St. Trina questline, but generally– and this applies to all NPC questlines, don’t be in a hurry to burn the Sealing Tree.

Think of burning the Sealing Tree as the DLC’s ‘Burn the Erdtree’ stage. It’s a point of no return and something you should only perform if you’re gearing up for the final boss. If you’ve burned it, tough luck– you’ll need to start the DLC again in NG+ or another character.

With that out of the way, and with the Sealing Tree still intact, let’s proceed to the St. Trina or Thiollier quest guide and walkthrough.

Start With Thiollier in Gravesite Plain

You can go to Thiollier at the very start of the Shadow of the Erdtree DLC. He’s in the location I pointed out on the map.

Finding Thiollier and talking to Thiollier doesn’t exactly trigger the St. Trina questline, but unlocking the Site of Grace near him for convenience is almost mandatory. Now that you’ve found Thiollier, it’s time to look for St. Trina.

Finding St. Trina in Elden Ring

To find St. Trina, you need to go to the Cerulean Coast (southern region) first. I’ve marked the location on the map above. The green trail is for surface directions, the red trail is for underground directions. Here are additional steps in case you get lost:

1. Start in Castle Front (Grace) just before Castle Ensis.
2. Follow the green and red trail, and use torrent to jump down from the cliffs to the pond.
3. Look for a cave next to giant flower enemies. This cave leads to Ellac River Cave (Grace).
4. Continue south down the river until you reach Ellac River Downstream (Grace). Then keep going south. You will need to do some platforming with Torrent.
5. Keep going and once you see a Furnace Golem, run past it and follow the final green trail on the map image above. Voila, you’re now in Cerulean Coast.

To get to St. Trina from Cerulean Coast, follow the further directions below. Again, the green trail is surface, red trail is underground.

1. From the Cerulean Coast Grace, head south to the southernmost tip of the map.
2. Head inside the Fissure and progress through the area.
3. You’ll eventually fight the Putrescent Knight. Defeat it or leave it for later.
4. After defeating the Putrescent Knight, look for a cave in the boss area (Garden of the Deep Purple), St. Trina is there.

Completing the St. Trina Questline

The hard part is done now. You’re ready to talk to the NPCs after this point. Here’s what you need to do.

1. Talk to St. Trina once. She won’t say anything. If you haven’t defeated the Putrescent Knight, you can leave and proceed to step 2.
2. Return to Thiollier, and tell him St. Trina’s whereabouts. Rest in the nearby Grace.
3. Thiollier will move to the Garden of Deep Purple (or in the Stone Coffin Fissure if you haven’t defeated the Putrescent Knight). You must defeat the Putrescent Knight, of course.
4. Thiollier will move in front of St. Trina and fall half-asleep in the Garden of Deep Purple. Talk to him.
5. Talk to St. Trina and choose ‘Imbibe nectar‘ four times. You will die after each attempt. Make sure to pick up your Runes before imbibing again.
6. After the fourth imbibe, talk to Thiollier. Pass on St. Trina’s words to him. Keep trying until there’s no more new dialog.
7. Imbibe the nectar once more at St. Trina. Then go back inside her cave.
8. Fight Thiollier because he thinks St. Trina likes you better.
9. After defeating Thiollier, talk to him in the cave again to gloat or rub salt on his wounds or whatever, then return to St. Trina and imbibe the nectar once more.
10. Talk to Thiollier again, and pass on St. Trina’s words.
11. Imbibe the nectar at St. Trina again. She’ll finally repeat to you that you must kill someone important.
12. Talk to Thiollier again until he can only say “A-ah.“

That’s it, you’re done playing messenger boy for these two, finally. However, there’s more to this quest after you’ve burned the Sealing Tree.

[SPOILER ALERT] St. Trina Questline AFTER Burning the Sealing Tree

I don’t recommend burning the Sealing Tree merely for the St. Trina questline alone. Make sure you’ve exhausted or progressed the other NPC questlines too. Or it’s up to you since you’ll be able to finish others in subsequent playthroughs anyway.

In any case, here are the rest of the steps for completing the St. Trina questline.

1. After burning the Sealing Tree and progressing through the main quest, you’ll be fighting people whom you initially thought were your allies. Along them would be Needle Knight Leda.
2. During or before the Needle Knight Leda fight, make sure to summon Thiollier.
3. Once more, once you’ve reached Divine Gate Front Staircase (Grace), summon Thiollier again for the boss fight.
4. Thiollier will supposedly drop all his gear (armor and weapon) for you to take. Consider it your reward.

That concludes the St. Trina questline in Elden Ring: Shadow of the Erdtree.