Do you want to compare Mister Sinister with Viper? Discover the powers, weakness & weapons of Mister Sinister and Viper from Mister Sinister Biography and Viper Biography. Find out all about Mister Sinister and Viper.# Check out how is Mister Sinister unique and distinct from Viper. Discover their love interest, sidekicks, family tree and the movies and games list in which Mister Sinister and Viper have appeared. Find out everything about them here!