Thermal Pack is a one-slot attack Trinket in Mina the Hollower tied to Fian's rescue quest. It boosts Mina's damage after death or after exiting Underlab — the buff fades over time, then returns stronger. This guide covers the location, the step-by-step quest route, how the effect actually works, and whether Thermal Pack is worth keeping in your loadout.
Thermal Pack Quick Facts
| Attribute | Details |
|---|---|
| Type | Attack trinket (conditional burst-damage) |
| Slot Cost | 1 Trinket Slot |
| Effect | Boosts damage after death or exiting Underlab. Fades, then returns stronger. |
| Location | Ossex — Couples Quarters / Miner's Den, behind the Trinket Bazaar |
| Requirement | Rescue Fian from his cell at Bone Beach |
| Reward Source | Fian / Fiancé quest reward |
| Sell Value | 1,000 Bones |
Quick Answer
Thermal Pack is an Ossex Trinket reward tied to Fian's quest. To get it, rescue Fian from the cell in Bone Beach, then return to Ossex and enter the Couples Quarters / Miner's Den area behind the Trinket Bazaar. Thermal Pack boosts Mina's damage after death or after exiting Underlab. The buff fades over time, then returns stronger.
Thermal Pack Location
Thermal Pack is found in Ossex, inside the Couples Quarters / Miner's Den area. This room is located behind the Trinket Bazaar — the shop run by Lady Susan near the central Ossex fountain.
The Couples Quarters / Miner's Den door is not accessible when you first arrive in Ossex. It only opens after you have rescued Fian (also referred to as the Fiancé) from his cell at Bone Beach.
How to Get Thermal Pack Step by Step
Getting Thermal Pack requires completing a specific rescue quest that spans two major areas: Bone Beach and Ossex. Follow the steps below in order.
Step 1: Reach Bone Beach
Travel to Bone Beach, the skeletal shoreline area accessible from Ossex. If you have not yet unlocked the Bone Beach route, progress the main story until the path east of Ossex becomes available.
Step 2: Rescue Fian from the Bone Beach Cell
Explore Bone Beach until you find Fian locked inside a cell. Interact with the cell to free him. This is the critical trigger — if Fian has not been rescued, the Couples Quarters / Miner's Den door in Ossex will remain closed.
Fian (the Fiancé) is part of a side narrative tied to Ossex. Rescuing him does not require a key item or boss kill — you simply need to reach his cell location and interact with it.
Step 3: Return to Ossex
After freeing Fian, travel back to Ossex. The fastest route is to use the nearest fast-travel point or walk back through the connecting path. Upon returning to Ossex, the game registers that Fian has been rescued and the Couples Quarters / Miner's Den door becomes accessible.
Step 4: Enter Couples Quarters / Miner's Den Behind the Trinket Bazaar
From the central Ossex fountain, head to the Trinket Bazaar — Lady Susan's shop on the west side. The Couples Quarters / Miner's Den entrance is behind the Trinket Bazaar, through a door that was previously locked.
If the door is still closed, confirm that you:
- Have reached Bone Beach and physically interacted with Fian's cell
- Have returned to Ossex after the rescue (not before)
- Are checking the correct door behind the Trinket Bazaar, not a different Ossex building
Step 5: Collect Thermal Pack from Fian
Inside the Couples Quarters / Miner's Den, you will find Fian. Speak to him to receive Thermal Pack as your quest reward. The Trinket is added directly to your inventory and can be equipped from any Underlab loadout station.
Thermal Pack Effect Explained
Thermal Pack's in-game effect reads:
Boosts damage after death or exiting Underlab. Fades, then returns stronger.
This is a conditional burst-damage effect, not a permanent Attack boost. It activates under two specific circumstances: when Mina dies and respawns, or when Mina exits an Underlab save room. In both cases, Mina receives a temporary damage increase.
How the Death / Underlab Damage Buff Works
The buff from Thermal Pack follows a fade-and-return pattern:
- Activation — The buff triggers when Mina dies or exits an Underlab.
- Fade phase — The damage boost gradually diminishes over time after activation.
- Return phase — After fading, the buff returns at a stronger level than before.
Community testing suggests the buff cycles through this fade-and-return pattern multiple times, with each return applying a stronger damage multiplier than the previous cycle. The exact buff percentages and duration of each phase have not been officially confirmed by the developers, so treat any specific numbers from community sources as approximations.
Because the effect relies on death or Underlab visits, Thermal Pack rewards a risky, aggressive playstyle — the more you die and respawn, the more opportunities you have to trigger the buff. However, repeatedly dying to stack the buff is not always practical in longer boss fights or areas with distant checkpoints.
Is Thermal Pack Worth Using?
Thermal Pack is a conditional burst-damage Trinket that shines in specific scenarios, but it is not an always-on Attack Trinket. Whether it is worth a slot depends on your playstyle and the encounter.
Thermal Pack is strong when:
- You are progressing through an area with frequent Underlab checkpoints, giving you regular buff triggers
- You are comfortable with a higher-risk playstyle that accepts deaths as part of the strategy
- The encounter allows you to die and return quickly without losing significant progress
- You want a damage spike for a tough room or gauntlet section where deaths are likely
Thermal Pack is weaker when:
- You are attempting a deathless or low-death run
- The area has long distances between Underlab checkpoints, limiting activation opportunities
- You need consistent, predictable damage output rather than cycling buffs
- You have other Attack Trinkets that provide reliable, always-active bonuses
On its own, Thermal Pack is situational. In the right build — especially one that leans into frequent Underlab visits or expects deaths as part of the strategy — it can provide meaningful burst damage when you need it most.
See how Thermal Pack compares with other Attack and situational Trinkets in our Trinkets tier list.
Best Builds for Thermal Pack
Thermal Pack works best when paired with Trinkets and strategies that complement its conditional activation pattern:
- Desperation Bonnet — Another Trinket that rewards low-health or high-risk situations, potentially stacking with Thermal Pack's death-triggered buff
- Smelling Salts — Provides a straightforward Attack boost that can help between Thermal Pack's fade cycles
- Bone Charm — A Bone Beach thematic Trinket that may synergize well for players running a death-heavy route through the same region
- Volatile Beastium — Adds another layer of conditional burst damage for players who enjoy managing cycling buffs
For exploration-focused sessions, consider swapping Thermal Pack out for a mobility or utility Trinket. The buff is most valuable in combat-heavy stretches and boss runs where Underlab visits are frequent.
FAQ
Where is Thermal Pack in Mina the Hollower?
Thermal Pack is in Ossex, inside the Couples Quarters / Miner's Den area behind the Trinket Bazaar. The door only opens after you rescue Fian from his cell at Bone Beach.
How do you get Thermal Pack?
Rescue Fian (the Fiancé) from his cell in Bone Beach, then return to Ossex and enter the Couples Quarters / Miner's Den behind the Trinket Bazaar. Speak to Fian inside to receive Thermal Pack as a quest reward.
What does Thermal Pack do?
Thermal Pack boosts Mina's damage after death or after exiting an Underlab. The buff fades over time, then returns stronger. It is a conditional burst-damage effect, not a permanent Attack increase.
Is Thermal Pack good?
Thermal Pack is a solid conditional burst-damage Trinket for aggressive playstyles and areas with frequent Underlab checkpoints. It is less effective for deathless runs or players who prefer consistent, always-on damage bonuses.
Is Thermal Pack missable?
Thermal Pack appears to be tied to Fian's rescue quest. If you progress past Bone Beach without freeing Fian from his cell, you may need to return to Bone Beach and complete the rescue before the Couples Quarters / Miner's Den door opens in Ossex.
Is Thermal Pack from Fian or the Fiancé quest?
Thermal Pack is the reward from Fian (also referred to as Fiancé in some community discussions). The two names refer to the same character — the NPC you rescue from the cell at Bone Beach and later meet in the Couples Quarters / Miner's Den in Ossex.