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Also, wasn't the langya bang on a long shaft? Does the jian (mace) have spiked metal coming out of the edge?
The jian 锏 is strictly speaking not a mace, but rather a sword-shaped weapon that has a 'blade' that is blunt and thick rather than sharp-edged and thin. It was used for the same purpose as the mace - to injure armoured cavalry or knock them off the horse. The true Chinese mace is the chui 锤, which is a solid sphere on a long stick. The langya bang 狼牙梆 is different in having a more elongated head, like an oval rather than a sphere, with spikes on it. There is a double-headed version of the langya bang (with a handle between the two heads) called the chu 杵 (pestle).

Langya bang on the left, chu on the right
A Warring States version of the mace head:

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I've also seen maces, primarily steppe troops, that looks similar to gears. What was that called?
That's the guduo 骨朵, or more specifically the jili guguo 蒺藜骨朵, as not all guduo have spikes.

A pair of chui on the left, and a guduo on the right