Crawl, called Guardon (ガードン) in the Japanese manual, is a badnik from the 16-bit version of Sonic the Hedgehog 2 found in Casino Night Zone. It has a bumper included, so if you try to perform a spin attack from the front it'll bump you away! So, you have to jump over it and quickly attack from the back as the only method of destroying it.
It has also appeared in Sonic 4's Casino Street Zone little change in design. And the attack pattern is exactly the same of the classic games.
Also appears in Sonic Lost World. In the version of Wii U it appears in the casino area (Zone 3) for Frozen Factory, in Zone 4 of Silent Forest and in Zone 3 of Lava Mountain. It keeps the same design ever. In 3DS version of it can be found in Sky Road in Zones 1 and 2, and in this version they have a unique special attack projectiles create waves.