AncientGreymon

AncientGreymon is an Ancient Dragon Digimon whose name and design are derived from "Ancient" and "Greymon". It possesses the attribute of "Flame", and is one of the legendary "Ten Legendary Warriors" that saved the ancient Digital World. It is told that its strength surpasses that of current Megas, and it is certainly a "Mega" being. Its abilities were later passed on to the "Dragon Digimon" of the Greymon-species. It is said that in the previous crusade, it survived to the end alongside AncientGarurumon, and sealed away Lucemon.

Digimon World 3
AncientGreymon appears when Diaboromon and Imperialdramon Paladin Mode DNA digivolve during battle.

Digimon Story: Lost Evolution
AncientGreymon digivolves from MetalGreymon provided the Spirit of Fire plate is set. It can be found in the Task Canyon after the ending.

Digimon Story: Super Xros Wars: Red/Blue
AncientGreymon can be scanned from a DigiMelody as a Dragon-type, Mega-Level Digimon. It can also be obtained during a battle by DigiXrosing Agunimon, Paildramon, MasterTyrannomon and MetalGreymon L. It'll attack with "Omega Burst".

Attacks
 * Gaia Tornado: Gathers the spirit of the land and creates a tornado to swallow up the opponent and blow them away.
 * Omega Corona (Omega Burst): Induces a super-detonation over the surrounding kilometers alongside an intense flash.