From publisher blurb:
Adventure gaming ideas have moved on a great deal. Our concept of what’s acceptable in fantasy has moved on from the medieval period more into the renaissance and restoration eras. That means firearms, which have often been eschewed in traditional fantasy for one reason or another, but in many ways firearms make a great deal of sense. Magic has already affected the changes that firearms did in the real world, reducing the effectiveness of armour and fortification, allowing ships to project force at great distance – even from off shore.
Like crossbows supplanting longbows, firearms democratised firepower. They didn’t require a huge amount of skill – despite being more technical and fiddly in many ways – and a man could be armed and fire en masse with other to devastating effect very swiftly.
Besides, guns are just fucking cool. Loud noises, clouds of smoke, devastating musketballs, the potential for new kinds of magic and explosives.
The mistake that seems to occur in a lot of games is making the guns too powerful, too close to modernity. Guns start to stop being appropriate to fantasy once you get to revolvers (discounting the Barsoomian influence) and the best balance seems to be guns no more advanced than those found in the sixteen and seventeenth centuries.