Thiollier's journey through the Realm of Shadow is one of the most mechanically rewarding NPC paths in Elden Ring: Shadow of the Erdtree. Unlike many NPCs who provide generic equipment, Thiollier’s quest offers unique utility items, high-tier Spirit Ashes, and a weapon that defines the "Eternal Sleep" meta. Navigating this path requires careful decision-making, particularly regarding the choice involving the Dragon Priestess, which can lock you out of specific rewards for an entire playthrough.

Initial Rewards at the Pillar Path Cross

Finding Thiollier at the Pillar Path Cross, southeast of the Castle Ensis front gate, provides immediate access to specialized poison equipment. This is the first opportunity to acquire the Deadly Poison Perfume Bottle. This weapon scales primarily with Dexterity and is essential for early DLC builds focusing on rapid poison buildup.

Beyond basic trading, the first narrative reward is Thiollier's Concoction. This key item is obtained after retrieving the Black Syrup from Moore at the Main Gate Cross. While Thiollier intends for this to be a means of "ending his weariness," for the player, this concoction serves as a pivotal tool for a major quest branch. If consumed by the player, it results in instant death, though you can purchase additional doses from Thiollier for 30,000 runes each. Its primary value lies in its use as a gift to another NPC.

The Dragon Priestess Branch: Ancient Dragon Florissax vs. Flowerstone Gavel

One of the most significant rewards linked to Thiollier’s questline isn't actually his own equipment, but rather the fate of the Dragon Priestess at the Grand Altar of Dragon Communion. Before defeating Bayle the Dread, players can choose to give the Priestess the Thiollier’s Concoction during the night.

Choice A: Administering the Concoction

If you give the Priestess the concoction and then defeat Bayle, you can return to find her slumbering. Upon her awakening, after several dialogues where she realizes her "god" (Placidusax) has seemingly forsaken her, she will eventually agree to accompany you.

  • Reward: Ancient Dragon Florissax Spirit Ash. This is widely considered one of the best support Spirit Ashes in the game. Florissax uses dragon cult incantations, specifically Flowerstone Lightning, and provides a massive defensive buff to the player, reducing incoming damage by approximately 10-15%.
  • Reward: Dragonbolt of Florissax. An incantation that further bolsters damage negation.

Choice B: Completing the Priestess Quest Normally

If you ignore Thiollier’s Concoction and assist the Priestess in her original goal by defeating Bayle, you receive different items.

  • Reward: Priestess Heart. This allows the player to transform into a dragon-humanoid form, boosting Dragon Communion incantations but requiring the removal of all armor.
  • Reward: Flowerstone Gavel. An Arcane-scaling hammer that reduces enemy lightning resistance, making it a staple for lightning-themed builds.

Choosing the Spirit Ash is generally recommended for players seeking longevity and support, whereas the Heart and Gavel are superior for specialized offensive casters.

The Southern Shore and the St. Trina Ritual

Once the Great Rune of Miquella shatters, Thiollier moves to the Stone Coffin Fissure at the southernmost point of the Cerulean Coast. Progressing through this subterranean dungeon leads to the Putrescent Knight boss fight. While the boss yields its own Remembrance, Thiollier’s presence here triggers the next phase of his rewards.

In the Garden of Deep Purple, players encounter St. Trina. To progress Thiollier’s quest, you must engage in the "Imbibe Nectar" ritual. This involves dying repeatedly to hear St. Trina’s voice.

  1. Imbibe 1-3 times: Instant death, no dialogue.
  2. Imbibe 4 times: St. Trina delivers her first line of dialogue regarding Miquella.
  3. Imbibe 6 times: Complete dialogue exhaustion.

After sharing St. Trina’s words with Thiollier, he becomes consumed by jealousy. This leads to the Thiollier Invasion.

Reward: St. Trina’s Smile (Talisman)

Upon defeating Thiollier’s invading spirit, you receive the St. Trina’s Smile talisman. This is a critical item for Sleep-focused builds. It increases attack power by 20% for 30 seconds when sleep is triggered in the vicinity. This functions similarly to the Lord of Blood's Exultation but for the Sleep status. Given the addition of "Eternal Sleep" in the DLC, this talisman allows for massive damage windows against vulnerable enemies and certain bosses.

Late-Game Assistance and Summoning Bonuses

While not a physical item in your inventory until the very end, one of the greatest "rewards" for finishing Thiollier's quest before burning the Sealing Tree is his availability as a summon.

  • Cleansing Chamber Anteroom: Thiollier can be summoned to assist against Needle Knight Leda and her allies. This fight is notoriously difficult due to the number of NPCs involved; having Thiollier’s poison and sleep support can significantly tilt the odds in your favor.
  • Final Boss Fight: If his quest is completed, Thiollier’s summon sign appears inside the arena for the final boss of the expansion. While summoning NPCs increases boss HP, Thiollier acts as a durable tank and occasional distraction, which is invaluable for players struggling with the final boss's aggressive second phase.

The Final Payout: Thiollier’s Full Set and Weapon

After the final boss of the Shadow of the Erdtree expansion is defeated, the ultimate rewards for Thiollier’s questline can be collected. His body will be found within the final arena.

Thiollier’s Hidden Needle (Fist Weapon)

This weapon is the crown jewel of the questline. It is a Fist weapon that primarily scales with Dexterity (B) and Intelligence (C) at +10 upgrade levels.

  • Passive Effect: Causes Sleep buildup (42 per hit).
  • Unique Skill: Eternal Sleep. This skill is a thrusting attack that inflicts Eternal Sleep. Unlike standard sleep, Eternal Sleep prevents most common enemies from ever waking up unless hit by a significant attack, and even then, some remains incapacitated.
  • Strategic Use: The Hidden Needle is particularly effective in PvP and against high-health elite mobs. When paired with St. Trina's Smile, the damage output following a successful sleep proc is devastating.

Thiollier’s Set (Armor)

Interacting with his remains also grants the full Thiollier's Set, including his Mask, Garb, Gloves, and Trousers.

  • Thiollier’s Mask: This headpiece provides a flat +2 increase to Dexterity, which is useful for meeting weapon requirements without investing additional levels.
  • Visual and Defensive Stats: The set offers high resistance to Sleep and Madness, reflecting Thiollier’s lore as a master of toxins and devotee of St. Trina. It is a lightweight set, making it ideal for builds that need to maintain a light equipment load for fast rolling.

The Epilogue Reward: St. Trina’s Blossom

After completing the questline and defeating the final boss, there is one final, hidden reward. Return to the Garden of Deep Purple where St. Trina was located. In her place, you will find the St. Trina’s Blossom headpiece.

  • Stats: This headpiece increases your Maximum FP by 6%.
  • Utility: For casters or Ash of War-heavy builds, this is one of the most efficient headpieces in the game. It provides a significant boost to your resource pool without the harsh stat penalties often associated with the glintstone crowns found in the base game.

Missing Rewards: Fail States and Warnings

It is vital to note that Thiollier’s questline can be easily broken. If you progress to Enir-Ilim and burn the Sealing Tree before completing the nectar ritual and the Thiollier invasion at the Stone Coffin Fissure, he will disappear from the game. This results in the loss of the St. Trina’s Smile talisman and his summon sign for the final battles.

Additionally, if you kill Moore or fail to interact with him regarding the Black Syrup before the Great Rune breaks, obtaining Thiollier’s Concoction becomes impossible. This subsequently locks the player out of the Ancient Dragon Florissax Spirit Ash reward path. To ensure all rewards are secured, players should prioritize the Stone Coffin Fissure as soon as they reach the Cerulean Coast and complete all dialogue cycles with St. Trina before entering the final legacy dungeon.

Summary of Key Rewards

Item Name Type Key Benefit
Ancient Dragon Florissax Spirit Ash Top-tier damage negation support.
St. Trina's Smile Talisman +20% Attack Power when sleep occurs.
Thiollier's Hidden Needle Weapon Inflicts Eternal Sleep; high Dex/Int scaling.
Thiollier's Mask Armor Increases Dexterity by +2.
St. Trina's Blossom Armor Increases Max FP by 6%.

By following this path, players gain a comprehensive suite of items that enhance both survivability and offensive capability, particularly within the specialized niche of Sleep-based combat which sees a massive resurgence in the late-game meta of the Shadow of the Erdtree expansion.