The Whomp King appears just like normal Whomps, except that he is much larger in size, has a bigger bandage, and has a few more cracks.
Just like other Whomp's, the King Whomp will try to squish Mario by attempting to fall on him. Mario must Ground Pound the Whomp King three times to defeat him. In the 2010 Wii game Super Mario Galaxy 2, the Whomp King is the boss of the Throwback Galaxy, and in this game he uses Thwimps as secondary attacks.
The Whomp King only resides at the top of Whomp's Fortress in Mission 1.