Binding of Isaac: Rebirth Wiki

Bob's Rotten Head is an activated item.


  • Upon use, Isaac holds a poison bomb which can be thrown in the cardinal directions and explodes on impact.
    • 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.


  • 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 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 AfterbirthContinuum Continuum: Bob's Rotten Head can now travel through walls and appear out of the opposite wall, similar to a portal-type mechanic.
  • Removed in Repentance Cricket's Body Cricket's Body/The Parasite The Parasite: 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 Repentance Causes two smaller tears to appear and then explode. Tears do not look like the normal head.
  • 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.
  • 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 †Trisagion Trisagion: Explodes multiple times before reaching its target, dealing explosive damage and knockback to Isaac.
  • 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's head.
  • 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%.