Tyranno Kenzan (Tyranno Hassleberry in the english dub) is one of the main characters in Yu-Gi-Oh! GX. Although he appeared in the anime, he was not in the manga.
In his first appearance, he was a bully in Ra yellow who often stole the duel disks of duelists he beat in a duel. Judaii Yuki(Jaden yuki in the English dub) duels him and defeats him. This earns Judaii Kenzan's respect and becomes an ally.
This put him at odds with Sho Marufuji (Syrus Truesdale in the English dub), because both wanted to be Judaii's best friend. Kenzan plays with a dinosaur deck and has a fascination with dinosaurs. In fact when he was younger, he was in an accident and had his shin bone replaced with that of a dinosaur bone. This awakened great power in Kenzan, making him immune to Takuma Saiou's (Sartorius in the English dub) mind control and temporarily transformed him into a dinosaur duel monster.
thumb|Jaden vs. Hassleberry
Someone's freaking out
Hassleberry with his one-time love interest, Alice.
Kenzan, Sho, and Judaii enjoy tea from Alice
Hassleberry rescuing Aster Phoenix.
Kenzan and Sho
Hassleberry from behind
Hassleberry from behind 2
Hassleberry from behind 3
Playing a card
Kenzan and Judaii
Kenzan when he was a bully
Kenzan's and Sho's rivalry
Kenzan vs. Takuma
Must be pretty brave sticking your tongue out at someone bigger and stronger than you
Kenzan takes Sho's blanket
Kenzan and Sho become friends
Kenzan being restrained
bit by Karen
Kenzan and Johan save Sho
Eating fried shrimp
thumb|Watching a duel
What they saw could not have been pretty
Close-up of Kenzan's eye becoming reptilian
Dino powers activate
Kenzan becomes a dinosaur spirit
Kenzan in the video game, Yu-Gi-Oh! GX Spirit Caller