Rotating Block

Turning Blocks, also known as Flip Blocks and Rotating Blocks, are yellow, eyed blocks found in Super Mario World. If they're blocking passages, Mario or Luigi can destroy them using the Spin Jump. Interestingly, they seem to replace Brick Blocks in Super Mario World, and it is possible that all of Super Mario World ' s blocks are to be taken as Turning Blocks due to the fact that, upon close inspection, it seems as if the ? Blocks of Super Mario World have eyes identical to those of a Turning Block.

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. (Interestingly, 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, which are also square, yellow objects with eyes, may be based on Turning Blocks.

Trivia

 * As stated above, the ? Blocks of Super Mario World have eyes and may therefore be Turning Blocks. Because of their possession of eyes, the ? Blocks, like the Turning Blocks that contain items, give angry expressions (by moving their eyes to diagonal positions) when hit. Interestingly, though the ? Blocks lost their eyes post-Super Mario World, they have continued to give this angry expression when hit, making it possible that all ? Blocks nowadays are related to Turning Blocks.