Binding of Isaac: Rebirth Wiki
Binding of Isaac: Rebirth Wiki

Added in Repentance

Ultra War is a boss added in The Binding of Isaac: Repentance and is the third of the Ultra Harbingers fought before The Beast in Home Home.


Phase 1[]

Ultra War charges in from the side of the screen and has two attacks which it alternates between:

  • Throws a large, Giga Bomb that deals contact-damage and explodes mid-air in a cross pattern that spreads across the entire screen similar to 15►Bomber Boy Bomber Boy Bombs. The Bomb also releases a burst of 8 lines of 4 projectiles in the cardinal and diagonal directions when it explodes. This attack is repeated 3 times.
  • Charges off-screen, then wraps around the bottom of the screen 3 times creating 4 to 6 pillars of harmless light in alternating positions across the screen from which large lava projectiles launch upwards with staggered timing.

Phase 2[]

Ultra War dismounts from its hobby-horse and has two new attacks which it alternates between:

  • Chases Isaac, then lunges diagonally downwards in Isaac's direction. After, Ultra War releases 4 streams of fire in the cardinal directions as well as a small burst of slower moving fires in all directions. This attack is repeated 2 times.
  • Lunges diagonally downwards while holding a large bomb which explodes in a cross pattern that spreads across the entire screen. Ultra War then bounces across the sides of the screen 3 times while moving upwards before plummeting into the lava below. When Ultra War emerges, it creates 4 to 6 large lava projectiles which launch upwards with staggered timing.
  • Upon death Ultra War explodes which can damage Isaac at close range.



  • If Isaac has the Safety Scissors Safety Scissors, the Giga Bombs Ultra War throws will be defused and fail to explode, after which they can be picked up or left to fall into the lava.
  • Ultra War's Giga Bombs can be killed by 15►Euthanasia Euthanasia shots.
  • The lava projectiles can be slowed and knocked down with certain slowing items such as Censer and high knockback tears.


  • Ultra War, like the other Ultra Harbingers is an upgraded version of its regular counterpart, War.

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Chapter 1
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???The LambMega Satan
The Void
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Greed Mode
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