These once-children creepy monsters wander around the crypt where all of them were savagely knifed and buried thousand of years ago, during the crusades. They were sent into battle, believed by those who sent them that the natural innocence of children whould protect them and lead to victory, but this never happened. Instead, all children were slaughtered and then buried. Then, resurrected by the source of evil, the children realized their new horrible condition and have been struggling for hundreds of years.
Children crusaders adopt two very different shapes: They fly around the crypt in spectral form, going through matter. While in this form, they can't attack, but they are invulnerable. When they spot the enemy, they start flying around it, looking at it from close distance. Suddenly they switch to physical form and start attacking using their unnaturally large veins they have instead of arms. They use veins like whips hitting and poisoning enemy with their corrupted blood. Also they have the ability to switch back to spectral form if they feel they are in danger, so it's critical do not give to them enough time to do so, it's critical to finish them off really fast. These enemies are able to switch back to their spectral form when they feel in danger.