From the Super Mario Wiki
Big Guy the Stilted is a giant Stilt Guy robot operated by Shy Guy in Yoshi's Island DS. He is found in his castle, along with many Shy Guys. To defeat him, Yoshi must use eggs (or Baby Bowser's fire breath) to knock Big Guy the Stilted off the edge of the platform they are fighting on, which is surrounded by lava, giving the Yoshi a chance to Ground Pound him. Many Shy Guys are inside this robot, jumping out occasionally making for an easy egg supply. After three Ground Pounds, it cracks, exposing all of the Shy Guy operators, after which it falls into the lava.
Names in other languages
||"Maskéchasse" is a portmanteau of Maskass, the French name of the Shy Guys, and échasse (stilt); Géant means "giant".
- Big Guy the Stilted may have been planned to be a real Shy Guy instead of being a robot, as a beta image of it shows it almost devoid of the patches and robotic features that covered it in the final game. However, one patch is discretely visible even in this screenshot, indicating that the reason for his lack of robotic features in the screenshot may have simply been because his sprite was incomplete at the time the screenshot was taken.