Gray Wolf (also known as Silver Rygar in Japanese) is the younger brother of Tiger on Monster Rancher. He was captured by Moo, who made him into a Baddie. He then became one of Moo's Big Bad Four.


Gray Wolf was once insecure monster whom jealous with his brother Tiger. Tiger tried to help him stand up for himself and steady in harsh world they live in, but was conflicted due to the latter's hestitation. This jealousy caused Master Moo after Gray Wolf and took him away, mustered his inner jealousy and misguided hatred on his brother so he become an ideal Baddie.

As Baddie, Gray Wolf was bitter and cruel, but still retained his feelings for his brother. He tried to recruit Tiger for Baddies' cause, but fails and this irritated him. Gray Wolf also ridiculed friendship and courage that Tiger build with others. When he was defeated, Gray Wolf revert to his former self and realized that his brother's friendship indeed genuine when compared to his Cabalos squad's loyalty as they flee upon his downfall and grateful that his brother stopped him.

Powers and Abilities

Being a monster of the same type with his brother Tiger, he mastered same abilities with the latter. He excels in performing Lightning (zaps his opponents with bolts of electricity fired from his horns), Blizzard (breathes an ice beam) and Tornado (conjuring a tornado). He can also perform melee attacks with claw, horn, and tail. He also learned a tail attack to temporarily blind the opponent by slapped it to their eyes from Tiger.


Monster Rancher

Gray Wolf leads a pack of Cabalos. After many failed attempts to destroy the Snatchers, Gray Wolf challenged Tiger to a fight to the death. They appeared evenly matched, but when they were supposed to use their claws, instead Gray Wolf whipped Tiger in the eyes with his tail, blinding him. He beat Tiger up, but as he moved in for the kill, Tiger sensed the vibrations and stabbed him in his Baddie crest destroying it, which turned him good again but mortally wounded him due to the crest bonded with his lifeforce. The brothers reconciled before Gray Wolf died and turned to a lost disc.

He was revived as a mystery disk when Moo was destroyed, and was unlocked by a girl named Nina in Season 3. Thanks to Phoenix's ability to undo Moo's corruption, Gray Wolf now no longer evil and is on friendly terms with Tiger.