Binding of Isaac: Rebirth Wiki

Scolex is a boss that can appear in the WombWomb and the (except in Rebirth)Scarred WombScarred Womb.

Behavior[ | ]

Scolex is only vulnerable in his blinking tail segment. He burrows into the ground before performing the following attacks:

  • Jumps out of the ground towards Isaac, burrowing back into the ground at the end of the jump.
    • If Scolex is hit by an explosion while mid-air, he will be deflected backwards.
  • Partially emerges head-first and shoots out a cluster of projectiles towards Isaac, similar to Boss Monstro ingameMonstro, but with a wider spread.
    • After performing this attack, Scolex will always jump out of the same spot he entered.
  • Partially emerges tail-first and fires cluster of 3 red Collectible Ipecac iconIpecac shots towards Isaac.
    • After performing this attack, Scolex will always jump out of the same spot he entered.

Scolex deals a whole heart of contact damage.

Champion Versions Needs to be unlocked[ | ]

(except in Repentance)Black: Scolex is 15% larger, slower, and has 25% more HP (375).

Gallery[ | ]

Notes[ | ]

Trivia[ | ]

  • Scolex appeared in the original The Binding of Isaac.
  • Scolex is the only Boss to have lost access to a Champion variant in an update. Specifically in Repentance, where his dark grey counterpart is inaccessible unless using Console commands to summon it.
  • Scolex can be considered an older or younger version of Boss Pin ingamePin, but not a posthumous one (that title goes to (except in Rebirth) Boss The Frail ingameThe Frail).
  • A scolex is the name of the head of a tapeworm.
  • Compared to the original Binding of Isaac, Scolex's head and tail attacks are swapped.
  • Scolex bears some resemblance to a mythological Mongolian Death Worm, which are described as long, scaly, and blood red. It also raises half its body out of the sand and covers its prey with a lethal acidic substance, which is somewhat similar to Scolex's head attack.

Bugs[ | ]

Bug Bug! When Scolex is slowed, some of his body parts may detach or won't even show up - they will only be visible while entering the ground (especially the tail).
Bug Bug! If the final vulnerable segment of Scolex's tail is destroyed using the Chaos CardChaos Card, the boss will glitch and become harder to kill. The tail will appear again if his head gets bombed or he hits Isaac.
Bug Bug! If you petrify Scolex (with Collectible Mom's Contacts iconMom's Contacts or other similar items) when it is in mid-air, you can damage any segment of its body.
Bug Bug! If you fire immediately upon entering the Boss Room, rarely, you can damage Scolex before it emerges.

The boss may also deal unavoidable damage sometimes if you immediately walk into the middle of the room after entering it.

Bug Bug! (in Afterbirth † and Repentance) If Scolex is under the effects of Collectible Broken Modem iconBroken Modem in mid-air, his jump will be stopped and he will fall.
Bug Bug! If Scolex is frozen with Collectible Midas' Touch iconMidas' Touch or (in Afterbirth † and Repentance)Collectible Dad's Ring iconDad's Ring and attacked, he can split into two halves, one with his head and one with his tail.