Chopper Block

Chopper Block (ダメージブロック)  is an obstacle that appears in Sonic the Hedgehog series. Found in Special Stages or Bonus Stages, these hazardous blocks can snatch Rings from the player.

Description
Chopper Blocks are booby-trapped blocks with either rectangular or round-shaped holes on top. These holes have sharp hatchways, which keep constantly chopping the hole's hatch.

Sonic the Hedgehog CD
In Sonic the Hedgehog CD, Chopper Blocks are found in every Special Stage terrain on series of row lines. If Sonic passes through lines of Chopper Blocks, he falls flat on his face, that will also reduce his running speed at complete stop. Chopper Blocks also rob Rings, which the player has collect in the Special Stage.

Even if the player's speed gets reduced, Sonic can also slip towards the water levels, which is possible if Chopper Blocks are placed close to water sections. The player has to keep avoiding these blocks by Spin Jumping over them.

Knuckles' Chaotix
Chopper Blocks appear in Bonus Stages of Knuckles' Chaotix, although their Japanese name goes under the different title Damage (ダメージ) in the manual. Here, Chopper Blocks are flying randomly and getting contacted on one, will subtracts 10 Rings from the player, as well reducing his/her time in the Bonus Stage.