Mysterious KnightMysterious Knight

The Lantern Key

You come upon a faintly glowing key and go to pick it up.

“Been looking all over for that key! Now if you don't mind...”

This person looks like bad news but maybe it's not good to be judgy.
The stranger thanks you for your help, and rewards you handsomely.
The stranger looks at you menacingly. It seems like only one of you is making it out of here with the key.
FightMysterious Knight 101 HPGold+10 to 20 for the win
Co-op voteOne vote is drawn, applies to all

What you can obtain

Card
RewardFor the win. Choice: Fight
Gold
10 to 100 GoldChoices: Return the Key / Fight

Where it appears

How ? rooms roll ›

What each choice does

Return the Key

Gain 100 Gold.

Gold+100
What the game says
The stranger thanks you for your help, and rewards you handsomely.

Keep the Key

Fight to obtain the Key.

What the game says
The stranger looks at you menacingly. It seems like only one of you is making it out of here with the key.

Which option to take

The key is worth it: in Glory it guarantees War Historian, Repy, which trades the key for two relics and two potions or for History Course.

Return the Key

Gold+100

Fight Keep The Key

Our pick
CardReward for the winFightMysterious Knight 101 HPGold+10 to 20 for the win
  • Fight if you can block about 21 on turn one and survive 30-plus damage turns while chewing through 101 HP behind Plating.
  • Take the gold when your deck is slow or your HP is low; losing this fight ends the run.

How it plays

Return the Key

  • Ends the event and pays 100 gold.

Keep the Key

  • Leads to a single Fight option, a combat against the Mysterious Knight: 101 HP (108 on Ascension 8) with 6 Strength and 6 Plating from the start.
  • He opens with Ram for 15 (17 on Ascension 9), then picks at random between War Chant for 3 more Strength, Flail for 9 twice (10 twice) and Ram again.
  • Flail and Ram can repeat twice in a row, War Chant never repeats, and every hit is raised by his Strength.

Winning

  • Winning gives normal combat rewards plus a Lantern Key card for each player.
  • The event does not resume after the fight.

Changes by version

  1. 13 Aug 2026PerformancePunch OffPlaytest
    Reduced hitch on Punch Off and The Lantern Key events
  2. 30 Jul 2026Bug fixPlaytest
    Fixed typo in Lantern Key event
  3. 2 Apr 2026Bug fixFoul PotionBeta branch
    Fixed an issue where, if the player visited a combat-style event without actually starting a combat (i.e. choosing "Return the Key" at The Lantern Key event) and then visited the Merchant immediately after, throwing a Foul Potion at the Merchant would not grant the player any gold
All 10 patch notes7 older
  1. 19 Feb 2026Bug fixInternal playtest
    The Lantern Key event's special card reward's text now fits properly into its button when playing in Korean
  2. 12 Feb 2026ChangeInternal playtest
    The Lantern Key is now a combat-room-style event
  3. 11 Dec 2025ChangeInternal playtest
    "Return the Key" option gold reward changed to 100 Gold
  4. 2 Oct 2025ChangeWar Historian, RepyInternal playtest
    Guarantees first Act 3 unknown room is War Historian, Repy event
  5. 7 Aug 2025Bug fixInternal playtest
    Players can no longer mash "Fight" choice in Lantern Key event
  6. 3 Jul 2025ArtInternal playtest
    Added temporary background art
  7. 5 Jun 2025ChangeHistory CourseInternal playtest
    Changed The Lantern Key event's History Course relic: no longer plays cards from two turns ago if you did not play cards the previous turn

Internal playtest notes are from before the Early Access release. Names and numbers in them can differ from the game today.

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