The "sledgehammer" you mention is called a "maul", and it's already in vanilla DF and masterwork. It's a civilian tool for splitting firewood, and in warfare was only ever used for engineering (such as putting in anti-cavalry stakes) and occasionally by archers and levies who had literally nothing better to use. If you think about how quickly you'd be fatigued swinging one, you'd see how useless a weapon it would be (pitchforks and knives were preferred) Generally warhammers had smaller heads than a modern claw hammer, but with a longer handle (especially if they were horseman's hammers) and a spike on the end for stabbing.
I know about the difference between mauls and warhammers, i was more referring to the weapon with a head like the long handled warhammer you mentioned, but with a shorter shaft, it was used quite frequently in the later medieval era when fighting often involved siegeing a fortress, the main advantage of the weapon was being usable to break walls/barricades like a maul, but the narrow contact point was good for breaking skulls.
hmm... ok so reading your post extra carefully i think i get what you mean, the halberd-esque one i was refereeing too was the one used by foot soldiers, the sledgehammer like one i was talking about was the cavalry one, and the shortened one i was talking about was like the crappy text art one from above, which was used in close combat.
im aware that warhammers are pointed weights, but the short blunt thing on a stick is also a warhammer. not a maul, mauls are war sledgehammers.
(P.S. i know quite a bit about ancient weapons, and i am well aware of the difference between fantasy weapons and RL weapons, please don't act haughty and imply otherwise, no offence, just most people start getting condescending towards me during a debate like this.)
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