A Mace is a one-handed melee weapon, and it is one of the few weapons which provide a Prayer awards, a trait shared by only a few other weapon-class items.
Maces are identical in attack speed and damage to scimitars and daggers. Prior to the Evolution of Combat, these weapons were not usually used, as they had a relatively slow attack speed and less damage than the more popular scimitars and shortswords. After the release, however, they began rapidly gaining popularity in Player killing scenarios, because of their Prayer bonus, as prayers are often used in PvP scenarios.
Players can get maces from bronze to adamant in Flynn's Mace Market in Falador. Rune maces can be purchased from the Champions' Guild. Dragon maces can be gotten from the Heroes' Guild and require the completion of the Heroes' Quest to be wielded.