Hornfel

Boss Portrait
Base HP	240
Base HP	240
Stage HP	0
Stage HP	0
Ingame Appearance
Entity ID	906.0
Found In	Boss
Dropped Items	Boss

Hornfel is a boss added in The Binding of Isaac: Repentance that can appear in the Mines.

Behavior

Phase 1

He appears with his own specially designed boss room, where the walls are covered in boss doors, with minecart tracks connecting them. Hornfel rides a minecart along these tracks and performs the following attacks upon entering the room:

• Occasionally, when Hornfel enters the room through a door, he is accompanied by 2 Fly Bombs.
• Throws 1-2 Bombs at Isaac. Additionally, each bomb has a small chance of having the Hot Bombs or Sad Bombs effect.
• Throws 3 Brimstone Bombs that resemble mines. Each has a delay and detonates after a few moments.
• Accelerates along one set of tracks, while frequently throwing out bombs for the duration. Slows down after multiple cycles, before getting sick and vomiting a fireball that release fire trails in the cardinal directions upon landing.
• Sends out 1-2 decoy dummies with 4 HP on other tracks that burst into 6 Troll Bombs if killed or walked into.
• Other minecarts occasionally appear on other tracks independent of Hornfel, carrying a Fire Place, TNT, or a variety of other enemies:

Bony

Faceless

Danny

Gurgle

Quakey

Hornfel and his decoys deal a whole heart of contact damage.

Phase 2

Once Hornfel has taken enough damage, he falls out of his minecart and attempts to escape from the room via one of the doors surrounding the arena. He makes no attempt to attack Isaac but he can still deal contact damage (Though this is reduced to half a heart from a whole heart).

• Other minecarts carrying other monsters and objects can still appear as usual during this phase.
• If Hornfel escapes successfully, the fight ends as normal.
• If Hornfel is defeated, he drops either 3 Bomb pickups, Boom!, Hot Bombs, Brimstone Bombs or Remote Detonator, and unlocks Brimstone Bombs if not already unlocked.

Gallery

• 

  Hornfel in-game.

• 

  Hornfel after losing his cart.

• 

  Hornfel fleeing.

• 

  Hornfel's decoy dummy.

• 

  Concept art of Hornfel and his behaviors.

Unlockable Achievements

• 

  Brimstone Bombs - After breaking Hornfel's minecart, kill him before he can escape.

Trivia

• Hornfel will sometimes taunt Isaac by sticking out his tongue while sending out his decoy dummies.
• Hornfels is the group name for a set of contact metamorphic rocks. They are known to be very hard and durable.
• The Horny Boys are a stitched amalgamation of Hornfel and Loki.

Bugs

Bug!	If Hornfel is killed off screen, the game crashes.

The Binding of Isaac: Rebirth
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