Wendy's Castle is the sixth castle in Super Mario World.
The level starts off with Mario avoiding a Dry Bones, jumping on a spring (also avoiding a Skewer) and moving on to where he has to avoid two Grinders. He needs to move forward and avoid two Lava Bubbles. Then avoid the next set of the Grinders and Skewers, get to the Midway Point and go to the next room. Mario then has to avoid the Hotheads and Sparkies and jump on the moving platforms to get to the Boss Door
Mario has to avoid two Zigzag Lava Bubbles in the fight. Mario needs to jump on Wendy O. Koopa three times to defeat her (she is the red one as seen in the image). Two yellow clones of her will also come out of the Warp Pipes so Mario has to make sure that he doesn't accidentally jump on them. Once Wendy O. Koopa has been stomped on three times, she falls into the lava, and Mario moves onto the Sunken Ghost Ship.