SkullMammothmon

SkullMammothmon is a Ghost Digimon whose name and design are derived from "Skull Mammothmon". It was a Mammothmon, revived from an ancient glacier, that continued to battle with Virus-species Digimon. As a result, its whole body was eaten away by a virus, and became nothing but bones. Despite dying, its survival instinct as a Vaccine was strong, and so in order to continue battling it exterminated the virus. However, it unexpectedly lost all of its emotions and intelligence beyond destroying Viruses. Even though its body has become nothing but bones, it continues to battle in safety because the DigiCore shining within its chest is undamaged.[2] However, if that bare DigiCore, thought to be its weak point, was struck, it would immediately be unable to maintain its vital functions.

In Ultima, SkullMammothmon.

Attacks
 * Spiral Bone Crusher (Spiral Bone): Rapidly spins and then hurls one of its vertebra.
 * Dash (突進 Tosshin?)
 * Gran Charge