Shy Guys are timid troublemakers and common enemies in the Mario and Yoshi series. They are famous for the masks they wear. Yume Kōjō: Doki Doki Panic, a non-Mario game, was the game they debuted in; they were later carried over to the Mario universe when Super Mario Bros. 2 was created. Shy Guys usually work for Bowser and the Koopa Troop, but they originally worked for the evil king Wart. Shy Guys make their first Mario game appearance in Super Mario Bros. 2. They attack Mario, Luigi, Princess Toadstool and Toad by walking in their general direction. They can be easily disposed by being picked up and thrown against another enemy or into a nearby abyss. They can also be defeated by having an object thrown at them.