A gray fetus, with a robotic eye.
Follows Isaac around, shooting enemies with a Technology laser with unlimited range. The shots pierce enemies just like Technology. Shots are fired in a straight line; they cannot be angled and don't provide any knockback.
- This item is excellent for killing enemies from a safe distance, especially against dangerous bosses and foes who don't have long range attacks. The laser will damage all enemies in a line, making it effective against tight groups of enemies (The Duke of Flies, for example).
- The downside is that Robo-Baby doesn't fire as often and doesn't provide knockback, thus making battles against monsters that chase Isaac more difficult (Lust or Gemini for example).
- The lasers fired can mimic Isaac's current tear effects, such as Mom's Contacts or Spider Bite.
- When Robo-Baby fires his laser at the same time as another "laser-shooting" enemy, such as Vis, the laser will become significantly larger, similar to having Technology and Polyphemus. However, it does not actually affect the damage of his laser.