|For his video game counterpart, see Dex Oyama.|
Dex Ogreon, known as Dekao Ōyama (大山 デカオ Ōyama Dekao) in Japan, is a character from the MegaMan NT Warrior anime series and the operator of GutsMan.EXE. He is the older brother of Chisao and a classmate of Lan Hikari, Maylu Sakurai, and Yai Ayanok, and a fellow friend of Tory Froid with the others. At the start of the series, he saw himself as a superior NetBattler than Lan, however, once Lan got MegaMan.EXE and the two easily beat GutsMan, he becomes his rival hoping to one day defeat him, though over the course of the series he drops this to become a curry chef for Number 1 Curry under Yahoot, though he still competes for the affection of Maylu with Lan (though Lan is often oblivious to how Maylu feels about him).
He appears in episode 48.
He appears in episode 5, watching on jealously as Netto talks to Meiru.