Dex Oyama

Dex Oyama, known as Dekao Oyama (大山デカオ) in Japan and Dex Ogreon in English anime and manga, is a character from the MegaMan Battle Network series. He is the rival of Lan and operator of GutsMan.EXE. He has a brother called Chisao. He believes that Dex is the best NetOp in the world and Dex tries desperately to maintain his respect.

Personality
Dex acts very arrogant and is boastful. He cares very much for Chisao, often panicking when he gets in trouble. Dex tries to maintain his respect in both the games and the anime. He also has a rivalry with Lan and the two compete in Netbattling and almost any other competition. However, they are also alike because they forget to do homework and do poorly in class. Dex also gets very mad when Maylu hugs Lan or shows any kind of affection for him at all. Dex cares deeply for his friends and is willing to risk his life for them. Dex has also been known to get emotional, like when he was going to move away to Netopia.

MegaMan Battle Network series
In the games, he and GutsMan can be fought in every game up to MegaMan Battle Network 4 for his chips. He often takes part in Lan's adventures, assissting him and sometimes needing to be rescued. Dex moves away to Netopia in MegaMan Battle Network 3 but returns later to help Lan fight the WWW. He appears to cheer Lan on during many ocassions and to hang out with him. Dex also provides some humor in MegaMan Battle Network 5, when displaying the Houdini of the beach. In MegaMan Battle Network 6, it is revealsed that he becomes mayor of ACDC Town.

MegaMan NT Warrior
Dex is Lan's rival, like in the games and always defeats Lan in Netbattles but after Lan's generic NetNavi is upgraded to MegaMan.EXE, he is easily defeated. Dex provides comic relief in many episodes. Once, he was taken to the hospital because a robotic cat bit his leg and wouldn't come off (and his hurt leg was repeatedly struck, either by dropping onto a surface or being bit again). He also has a crush on Mayl but is always turned down. He enters the N1 grand prix but is defeated.

In MegaMan NT Warrior Axess, he goes to another country with the ex-WWW members to work at their curry shop and train hard. When he comes back, he has a gung ho attitude and challenges Lan and MegaMan to a Netbattle. However, they are attacked by BurnerMan.EXE and MegaMan teams up with GutsMan to defeat him.

Trivia

 * Dex is one of the only two people to actually attempt to Cross Fuse but failed doing it. The other was the Cross Fusion Test Volunteer in Episode 1 of Axess