Turbo Spiker
From Sonic Retro
Turbo Spiker, or Yadorin Jet (ヤドリンジェット) in Japan, is a wheeled hermit crab robot found in Hydrocity Zone. They fire off their spiked shells when approached and start rolling back and forth. However, since they fire they shells right away, they can be easily destroyed with a spin or jump. It appears to be a more improved version of another badnik from Sonic the Hedgehog 2.