Binding of Isaac: Rebirth Wiki

Bob's Rotten Head is an activated item.


  • Upon use, Isaac holds a poison Bomb Bomb which can be thrown in the cardinal directions and explodes on impact.
    • The bomb can fly across the room for a range before falling to the ground and explode, a distance equal to that of Isaac's tears' if the player's current range is 9.50.
    • Removed in Repentance The explosion deals a flat 50 + Isaac's tear damage and poisons affected enemies.
    • Added in Repentance The explosion deals a flat 185 + Isaac's tear damage and leaves behind a gas cloud that poisons affected enemies. The poison cloud deals 5 damage.
    • Removed in Afterbirth The poison deals 6 or 8 points of damage over time.
    • Added in Afterbirth The poison deals 3 times Isaac's tear damage over time.
    • Added in Repentance It will bounce off walls slightly before exploding on the floor.
  • This item belongs to the Added in AfterbirthBob Bob set. Collecting three items from this set will transform Isaac into Bob.


  • This item can drop from Sloth Sloth.
  • Bob's Rotten Head is affected by many tear modifiers and some bomb modifiers. Notable exceptions and precautions are listed below.
  • Bob's Rotten Head cannot directly impact Beggar.png Beggars, Slot Machine.png Slot Machines, or Blood Donation Machine.png Blood Donation Machines, just passing through, but can destroy them with the blast damage if it impacts anything nearby and open Secret Room Secret Rooms, Super Secret Room Super Secret Rooms, or destroy rocks like any other bomb.
  • Certain interactions require Flat Stone to be effective or work.


  • Added in AfterbirthBob's Bladder Bob's Bladder / Bob's Curse Bob's Curse / Bobby-Bomb Bobby-Bomb / Added in AfterbirthBomber Boy Bomber Boy / Added in Afterbirth †Fast Bombs Fast Bombs / Added in AfterbirthScatter Bombs Scatter Bombs / Mr. Mega Mr. Mega: No effect.
  • Added in RepentanceBlood Bombs Blood Bombs: Bob's Rotten Head leaves a pool of red creep on the ground after each explosion.
  • Added in RepentanceBook of Virtues Book of Virtues: Spawns wisps in the middle ring. The wisps shoot arcing green tears with decreased range, with a 7.5% chance of firing an explosive, poisonous tear.
  • Added in AfterbirthCar Battery Car Battery: No effect.
  • Added in Afterbirth / Removed in RepentanceContinuum Continuum: Bob's Rotten Head can now travel through walls and appear out of the opposite wall, similar to a portal-type mechanic.
    • Added in Repentance No longer travels through the wall; instead he bounces off it, like with Rubber Cement Rubber Cement, and then travels for the rest of its duration and then explodes.
  • Added in AfterbirthHoly Light Holy Light: Has a chance to throw a Holy Light head that spawns a damaging beam of light dealing (Removed in Repentance4x) Added in Repentance3x the explosion damage when it hits an enemy.
  • The Parasite The Parasite: Causes two smaller tears to appear that explodes for half the damage of the head. Tears do not look like the normal head.
  • Cricket's Body Cricket's Body: Spawns four smaller heads that explodes for half the damage of the bigger one.
  • Added in Afterbirth / Removed in RepentanceExplosivo Explosivo / Added in Afterbirth / Removed in RepentanceSticky Bombs Sticky Bombs: If Bob's Rotten Head sticks to an enemy (sometimes with Explosivo, always with Sticky Bombs), the explosion is delayed but will deal 110 damage.
    • Added in Repentance No longer sticks to enemies.
  • Added in RepentanceFlat Stone Flat Stone: Will cause Bob's Rotten Head to bounce once, exploding twice and leaving two gas clouds.
  • Fire Mind Fire Mind: Creates fire when the head lands.
  • Godhead Godhead: Creates a Godhead aura around the head when thrown.
  • Added in Afterbirth †Haemolacria Haemolacria: When the head lands, tears are fired.
  • Rubber Cement Rubber Cement: Causes the head to bounce off of rocks and walls.
  • Sacred Heart Sacred Heart: Homing effect is applied.
  • Tiny Planet Tiny Planet: When used, Bob's Rotten Head will orbit the player similar to a tear.
  • Added in Afterbirth / Removed in RepentanceTrisagion Trisagion: Explodes multiple times before reaching its target, dealing explosive damage and knockback to Isaac.
    • Added in RepentanceShoots a white blast of light instead of the head that pierces through enemies, and causing explosions when it contacts an enemy (if not killing it at the first tick), an obstacle, or when it runs out of range. One tick of the beam deals 33% of Bob's Rotten Head's damage to enemies, but the resulting explosion every tick deals full damage.
  • Added in RepentanceUranus Uranus: Enemies are frozen when dying to Bob's Rotten Head.
  • Worm Trinkets: Bob's Rotten Head is affected by trinkets like Hook Worm Hook Worm and Wiggle Worm Wiggle Worm the same way tears are.

In-game Footage[]

Unlockable Achievements[]



  • The item's appearance is similar to Pestilence Pestilence's head.
  • Sloth Sloth's full name is Bob Sloth, revealed in a QnA. Because Sloth drops this item, it may be his head.


PC Normal mode only 6DKD WJZG (Treasure Room adjacent to spawn)

PC Normal mode only A7ZJ BFRD (Treasure Room adjacent to spawn)

Vita Y8JW A17S


Bug Bug! Although Bob's Rotten Head works normally with Butt Bombs and Bomber Boy has no effect, their combination drops the explosion damage by 50%.