Guren (prisoner)

was a prisoner at Orochimaru's Northern Hideout. He received a cursed seal in the course of Orochimaru's experiments.

Appearance
When activated, the seal resembles vines as it spreads across his body. In its level two state he grew wing-like protrusions from his forearms and a broad flat tail.

Abilities
He was able to enter the second state of the cursed seal, but was powerful enough to brutally massacre all the prison guards with just the first state.

Itachi Pursuit Arc
After the prisoners had heard rumours of Orochimaru's death and began to revolt, Guren escaped and after entering the first stage of his cursed seal, brutally killed a number of guards who tried to subdue him. He later escaped to the outside and attacked Sasuke and his group, he was however quickly defeated by Sasuke Uchiha.

Trivia

 * In the Viz manga and the Third databook his name was given as Glen instead of Guren.