Rotating Block

Turning Blocks, also known as Flip Blocks and Rotating Blocks, are yellow, eyed blocks found in Super Mario World. When hit from below, they spin around, allowing Mario and Luigi to pass through them. Super Mario and Super Luigi can destroy them by using the Spin Jump from above. They seem to replace Brick Blocks from previous Super Mario games, and can content items too. Some blocks disguised as Turning Blocks have items inside.

Turning Blocks reappeared in Super Smash Bros. Melee, on the Yoshi's Island stage. In this game, Turning Blocks were identical to their Super Mario World counterparts, only 3D (they would turn 2D when rotating). They also showed up in Super Princess Peach, where they looked the same but had a different purpose: rather than spinning and allowing entrance when hit, they broke and released an item when hit. Also, the Boards of Super Mario RPG: Legend of the Seven Stars; and Bike Pads from Mario & Luigi: Superstar Saga, being square, yellow objects with eyes, may be based on Turning Blocks.