Muppet villains

A villain (or a "bad guy") is an evil character in a story or film. The villain usually is the antagonist, a character who tends to have a negative effect on other characters. Random House Unabridged Dictionary defines villain as "a cruelly malicious person who is involved in or devoted to wickedness or crime; scoundrel."

The Muppet Movie

 * Doc Hopper
 * Max
 * Professor Krassman
 * Snake Walker

The Great Muppet Caper

 * Nicky Holiday
 * Marla, Carla, and Darla

The Muppets Take Manhattan

 * Martin Price

''Follow That Bird

 * Miss Finch
 * Sam Sleaze
 * Sid Sleaze

Muppet Treasure Island

 * Long-John Silver
 * Pirates

Muppets From Space

 * K. Edgar Singer
 * Rentro
 * Dr. Tucker

The Adventures of Elmo in Grouchland

 * Huxley
 * Bug
 * Pesties

Kermit's Swamp Years

 * Dr. Hugo Krassman
 * Mary

It's a Very Merry Muppet Christmas Movie

 * Rachel Bitterman

The Muppets' Wizard of Oz

 * The Wicked Witch of the West
 * The Flying Monkeys

The Muppets

 * Tex Richman
 * Uncle Deadly
 * Bobo the Bear
 * The Moopets

Muppets Most Wanted

 * Constantine
 * Dominic Badguy