Skorp
From Sonic Retro
The Skorp is a scorpion-like badnik found in Sandopolis Zone. These wheeled robots roll around the ground, and whip out their stingers when approached. It's a bit anoying to avoid it's attack, but if you do, jump/roll into the badnik to destroy it. A good tactic for defeating this badnik is to get within range, stop, jump over his tail, and spindash into him when he's bringing his tail back in.