Vicious

It's all in the name with Vicious: he is ruthless, bloodthirsty, cunning and ambitious, willing to do anything in order to secure a position of power. He is a member of the Red Dragon Crime Syndicate in Tharsis, and is often referred to or depicted as a venomous snake. His weapon of choice is not a firearm, but a katana which he wields skillfully, even against gun-wielders. After Spike's supposed death, Vicious also leaves the Red Dragons briefly to fight in the Titan War of 2068 although his precise motivations for enlisting are debated.

(Source: Wikipedia)