Vat-Born Mogadorians are Mogs that are grown in vats and used for battle. They are described as not very intelligent, but very strong. They are deathly pale, paler than a true born, and are rarely seen in daylight. Vat-borns have small, sharp teeth, being said by Adam in The Forgotten Ones that their smile is like a shark's. When they die, they disintegrate into ash. Adam says in The Revenge of Seven that they are meant to die like this, saying that they're "bred for combat, not for burial".
They are thought to be created from the same matter as the 'Augmentation' enhancement injections known as MogPro which causes parts of Mogadorian Soldiers, which have been injected, to disintegrate in a similar way when they die. In The Fate of Ten, the entity shows in a flashback that this substance is made of pure Loralite, but manipulated by a machine build by Sertrákus Ra, the Loric Pipeline