Shy Guys, alternatively formatted as Shyguys,[1] Shy-Guys,[2] or ShyGuys,[3] are common enemies in the Mario and Yoshi franchises. They are recognizable by their masks, which they wear due to their shyness.[4][1] Shy Guys made their first appearance in Yume Kōjō: Doki Doki Panic, a non-Mario game; they were later carried over to the Mario universe when Super Mario Bros. 2 was created. Shy Guys are especially common in spinoff games, but are comparatively rare in the mainline Super Mario series. They are voiced by Treehouse member Nate Bihldorff.