MegaDarknessBagramon

DarknessBagramon is the Final Antagonist in Digimon Xros Wars.

Appearance
DarknessBagramon is an Unknown Level Digimon that is the combined form of both Bagramon and his brother, DarkKnightmon. There are two version of DarknessBagramon, one where Bagramon takes over and one where DarkKnightmon takes over.

As DarknessBagramon (Bagramon)
In this form, DarknessBagramon looks excatly like Bagramon with DarkKnightmon's armor covering most of his body. He still has his giant skeletal arm, and leg. He also pocesses twelve giant black wings. His chest armor sorta has a skull shape.

As DarknessBagramon (DarkKnightmon)
In this Form DarknessBagramon looks excatly like DarkKnightmon with Bagramon's giant right skeletal arm and leg.

Digimon Xros Wars
After the Death Generals were defeated for a second time, Bagramon and DarkKnightmon decided to fight Xros Hearts head on. But DarkKnight betrayed Bagramon and absorbed him to become DarknessBagramon (DarkKnightmon). However Bagramon manage to take over and change their appearance to form; DarknessBagramon (Bagramon). DarknessBagramon manage to destroy both Shoutmon and the rest of the Xros Heart United Army. He then send them into dark void. By doing so, DarknessBagramon leaves the Digital World and manage to enter the human world.