Ball and chain (windup)
Maces are large, spikey balls on chains that appear in Super Mario World 2: Yoshi's Island and its sequel Yoshi's Island DS. There are a few different types of maces featured in these games. They typically appear in castles and forts.
The first type of mace is wound up by a Boo Guy that sits in the wall. Once it is wound up as far as it will go, the Boo Guy will let go and the heavy ball will drop. If the ball touches Yoshi, Baby Mario will fall off Yoshi's back and the timer will begin. The Boo Guys take some time to wind up these maces, giving Yoshi time to safely pass underneath.
Another type of mace, operated by more than one Boo Guy, resembles a spikey ball at the end of a long spikey pole. This mace revolves around in sweeping circles. Again, if Yoshi is hit, he will lose Baby Mario.
A sub-type of mace, also appearing in Yoshi's Island DS, is the "? mace." This type of mace has a wooden log on the end, which is covered in spines. To get past this obstacle, Yoshi must use his eggs to hit the question mark circle above the mace. This will then slowly lift the spikey wooden log, making it safe to pass. In Super Mario World 2, the chain this object is hauled up by is spikey, and therefore dangerous to touch; however, in Yoshi's Island DS, the chain was spike-less, making it safe to touch, but still impossible to cross. Therefore, this obstacle can only be passed by when the question mark is hit by enough eggs.
All three of these maces, as well as the Boo Guys that operated them, are invicible, so Yoshi must time his jumping in order to pass safely.
