Ultimate 4

The Ultimate 4 (アルティメット) are four extremely powerful grade Appmon and the supporting antagonists in Digimon Universe App Monsters. They are Leviathan's handpicked generals.

History
The Ultimate 4 were gathered by Leviathan to aid Knight Unryuji after he became L-Corp's CEO. They watch as Knight unleashes an L-Virus-infected over L-Town. They later show up to the App Drivers after Eri Karan refuses Knight's offer of working for Leviathan. They then fought the four of them, effectively winning, destroying their App Drives, and killing their buddies. Fortunately, Yujin and stepped in and sent the Drivers back to Earth before the Appmon got a chance to kill them.