Basic Information
A mace is a bludgeoning weapon with a attached striking head - as opposed to one carved from the haft as the striker of a club is. Generally this takes the form of a metal head on a wooden haft, although an all metal mace is possible1, as are heads of stone. The striking head adds mass and durability to the ancestral club but remains more easily handled than a maul and evidence of mace production can be found as far back as 12000 BC - first in bone and stone, and then in metal, where they remained useful for cultures who lacked the metallurgy to create blades. Maces can be one or two handed.
The shape of the head doesn't matter all that much - if it's mostly spikes the 'mace' is probably a morning star that's been mislabelled, but apart from that, almost anything goes. The archetypal mace in the Western tradition is probably tipped with a head shaped like an inverted bell made of blunt metal flanges, but blunt metal balls are just as credible and the ancient Egyptians seem to have used a mace with a disc shaped head.
Historically the mace was fairly popular as an additional weapon for European knights - having the usual advantages of a bludgeoning weapon against armour and being relatively easy to use. The equivalent Japanese weapon, known as the tetsubo or kanabo has significant presence as well - and, in Japanese folklore was the traditional weapon of the Oni, having connotations of brute force about it.
Rumour has it that medieval European clergymen used the mace on the battlefield to avoid spilling blood - this does appear to be almost completely rumour, partly because many of them are recorded as using swords and spears (such as the legendary Archbishop Turpin2 and the very real Hubert Walter3) and partly because anyone who has used a heavy, blunt object in melee will know that it's not bloodless. Nonetheless this rumour has meant that … some roleplaying systems … made blunt weapons (typically maces) a hallmark of the "cleric" class for several editions, even when it made no sense at all to do so.
The other "cultural" significance of the mace is as a symbol of office - opinions vary as to how it achieved this particular role4, but it seems to have it. The mace is used ceremonially in a variety of contexts including universities, the UK Parliament, marching bands and, of course, Royal Sceptres.
Confusingly Mace is also a brand name for a capsaicin based self defence spray.
Sources
Game and Story Use
- Utility will depend on how well your system models the weapon vs. armour dynamic.
- Expect the mace to be your best solution to the legendary monster with an unpierceable hide - Heracles choked the Nemean Lion, but only after stunning it with his club. Presumably if the club could stun it it could reduce the lion to a bag of mush as well, but this would not be the first time there were logic gaps in the Heracles myth.