There’s no limit on what you can build guns into, and we should know, because we’re humans: and humans are the best at putting guns into things where guns shouldn’t be. To that end, here’s a rundown of some stupid shit people have done with firearms, and rules to represent them in your run-of-the-mill D20 game:
Note: If you’re playing in Dungeons and Dragons or anything with a similarly fantastical feel, gunpowder and firearms are experimental at best. We can assume your system has some kind of malfunction rule – use it, but double the chance of misfire, because these things are daft.
This seems like top-drawer bollocks of the highest order, because it combines one of the least dangerous things you can still legally call a “weapon” with one of the most dangerous things, namely: a gun. Anyway, the Apache revolver is a British invention which starts off as a hard-to use knuckleduster and unfolds into a hard-to-use pistol, and it even comes with a bayonet on it, because that’s what every pistol needs, isn’t it.
(Pistol: D6+1 damage, range 10ft. “Bayonet:” D4, but you look like a bellend trying to use it. Knuckleduster: D3. (Warning: Knuckledust is lethal if inhaled, so wear a mask.))
The pen may be mightier than the sword, but both of them pale into insignificance next to the GUNPEN. It holds a single shot, it has a range about equal to throwing the fucking thing, and it takes several minutes to screw together. But it can propel a lump of metal into someone’s body pretty effectively so long as you stand next to them when you do it, so it’s not all bad.
(D6 damage, range 5ft, one shot.)
The gunpen is mightier than both the sword and the pen, but the gunsword takes the gunpen round the back of the stables and shoots it clean through the head. A fairly popular tactic from the 16th century onwards was to build a single-shot concealed pistol into your sword, shield, axe or wife and use it during battle to surprise your enemy. Of all the weapons on this list, this is probably the closest to something you’d like to use in a fight: at least it still functions as a sword if it misfires, which it probably will.
(D6 damage, range 5ft, one shot. If your enemy doesn’t know you hid a gun in your sword, +2 to hit.)
Here comes the bride – and she’s wearing a pistol on her finger! This ring-gun uses tiny bullets made by and for children, and boasts a barrel length of zero millimetres, making it more of an objet d’art than a usable weapon.
(D3 damage, range 0ft)
What time is it? TIME TO DIE. Yes.
(D6-1 damage, range 5ft)
The Nazis did a lot of stuff wrong – I don’t think we’re being too contentious saying that. That “stuff” includes building a four-shot revolver into a belt-buckle; sounds cool in principle, and you can imagine yourself standing feet shoulder-width apart, backlit in a door, firing it at a squad of mooks, crotch ablaze with smoking death. But that’s not how it’d go – you’d have to fiddle with it, ruining the element of surprise, so your murder options are pretty much limited to people who don’t get suspicious when they see you undoing your belt: i.e. sexual partners or someone else in the same bathroom as you.
(D6-1 damage, range 5ft. Make a Sleight of Hand check when using the Belt Buckle Gun to not have someone ask what the fuck you’re doing)
A DIFFERENT, LARGER GUN
Hey! You like guns? How about we stick a gun in your gun so you can gun while you gun? Is your gun not heavy enough? How about we strap a big shotgun to the underside. Or a grenade launcher! No more arduous switching between different weapons, or talking to people even: just shoot all day long. How many guns can we fit into a single gun? We’re still finding out!
(Profile as regular gun, but: damage is reduced by -1 and ammo count is halved. You can build a gun into a built-in gun, further reducing the damage and ammo count, and so on and so forth, until you run out of damage or bullets.)
This was never made, which is a terrible crime. Also, as the source says, the barrel looks to be a 50. Calibre, which would most likely break or at least really damage the firer’s neck.
(D8 damage, range 15ft, D4 damage to self upon firing)