Effect: Thorns damage has a 50% chance to explode, dealing AoE damage to nearby enemies. Each copy also grants +20 Thorns.
Unlock: As Athena, land the killing blow on a Stage Boss using Aegis
Quin's Mask is an Epic item that gives every Thorns damage instance a 50% chance to create an AoE explosion at the target's position. The explosion deals 50% of the original Thorns damage to all enemies within the blast radius. Every copy also passively grants +20 Thorns, which both increases the base damage of your spikes and increases the explosion damage proportionally - since explosion damage is always 50% of the triggering hit.
Three damage sources can trigger Quin's Mask explosions, per community testing at megabonkinfo.org: standard Thorns damage from enemies hitting you, Cactus item spikes, and Aegis shield shockwaves. Any of these that deal Thorns damage rolls the 50% explosion chance independently on each hit.
The explosion radius scales with the number of copies held and your Size stat multiplier using the formula (5 + copies) × Size multiplier, clamped between 1.0 and 10.0. Noelle's Size-per-level passive therefore directly increases Quin's Mask explosion radius throughout the run.
The 50% explosion chance stays fixed regardless of how many copies of Quin's Mask you hold. What stacking does is widen the explosion radius (via the formula) and raise the Thorns stat (+20 per copy), which increases both spike damage and explosion damage since explosion damage is always 50% of the triggering hit. Two copies gives 160 Thorns (vs 120 with one, assuming 100 base) and a wider explosion, not a higher proc rate.
| Property | Details |
|---|---|
| Unlock condition | As Athena, land the killing blow on a Stage Boss using Aegis |
| Stage Boss options | Any Stage Boss on any map works - Forest Tier 1 is easiest. Boss Curse totems spawn additional Stage Bosses if you want more attempts per run |
| Key tip | Athena gains +2 Thorns per level automatically, so she has Thorns even without Thorns Tome. Let Aegis's shockwave deal the final boss hit rather than your weapons |
| Purchase | After unlocking, buy with Silver from Main Menu - Unlocks - Items |
| Rarity | Epic |
Boss Curse totems spawn additional Stage Bosses mid-run. If your Aegis shockwave doesn't finish the first boss, Boss Curses give you more opportunities in the same run without restarting. Stack Boss Curses on Athena runs specifically targeting this unlock.
Athena - The wiki confirms Athena is the primary character for Quin's Mask, and she is the only character that can unlock it. Her Lock In passive gives +2 Thorns per level, scaling the triggering damage (and therefore the explosion damage) automatically throughout the run. Her Aegis weapon is also one of the three confirmed sources that can trigger Quin's Mask explosions, meaning every Aegis shockwave has a 50% chance to explode for AoE damage on top of the shockwave itself.
Sir Oofie - Sir Oofie's Reinforced passive adds +1% Armor per level. Spiky Shield converts Armor into Thorns at +2 per 1% Armor, indirectly compounding Quin's Mask explosion damage through the Armor-to-Thorns chain. Community guides specifically note that Armor Tome is often stronger than Thorns Tome in this build because Spiky Shield's conversion makes Armor upgrades do double duty - reducing damage taken and raising Thorns simultaneously. Sir Oofie's passive feeds that conversion every level.
Megachad - Megachad's AFK Aura playstyle keeps him stationary while swarms walk into contact range, generating consistent Thorns hits from enemy contact. His Flex passive also has a cooldown that can be reduced with attack speed, meaning more frequent invulnerability windows - and community discussion confirms Kevin + Quin's Mask on Megachad is a specifically noted build, where Kevin's self-damage procs Thorns hits and therefore Quin's Mask explosions without requiring enemy contact.
Each Thorns damage instance has a 50% chance to create an AoE explosion dealing 50% of the original damage to all nearby enemies. Each copy also grants +20 Thorns. The explosion radius scales with copies and your Size stat: (5 + copies) x Size multiplier, clamped between 1.0 and 10.0. The 50% explosion chance does not increase with more copies.
Play as Athena and land the killing blow on any Stage Boss using Aegis. Forest Tier 1 is easiest. Athena already has Thorns from her passive so you do not need the Thorns Tome. Let Aegis's shockwave deal the final hit on the boss rather than your other weapons. Boss Curse totems spawn extra Stage Bosses for more attempts per run.
Three sources trigger the explosion: standard Thorns damage from enemies hitting you, Cactus item spikes, and Aegis shield shockwaves. All three are confirmed by community testing at megabonkinfo.org. Each is an independent 50% roll per hit.
Yes. Each additional copy adds +20 Thorns and increases the explosion radius via the (5 + copies) x Size formula. The 50% explosion chance itself stays at 50% regardless of how many copies you hold - stacking improves damage and radius, not proc frequency.
