These seem to come in three broad varieties:
- Enhanced weapons: these are those where the magic makes them better at doing whatever they would normally do - the sword is sharper the … well, in legends it's mostly swords, but there are also things like super accurate bows and thrown weapons which return to the user. That sort of thing. There are also structural enhancements that make weapons more durable and what have you that fit nicely into this category. The simplest enhancement is probably that which allows the weapon to harm things that normal weapons can't harm - the immaterial (like ghosts) or those with supernatural protection or healing that would make regular weapons ineffective. Infinite supplies of ammunition may also be included - although until at least the revolver appears, this is more likely to be a feature of a magical ammunition pouch instead.
- Secondary effects: these are over and above the primary function of the weapon and include both things like weapons that wreathe themselves in fire and those that make the user invisible/able to fly/extra strong or do things like detecting enemies, shedding light or giving advice.
- Purely magical attacks: these devices have little or no mundane damage dealing ability and either shoot magic blasts at the target or have some more insidious effect such as paralysis or curse sending.
Origins may vary - a weapon may draw its powers from the materials of construction (or those used in the manufacturing process), from spells worked on it during the forging process or afterwards, or from the character of the maker or long term user. In some traditions, a weapon may also have a spirit or demon dwelling within it, whether by choice or otherwise - Western traditions might limit this to the most powerful of blades, but more animistic cultures might consider it only natural that something that has been made with great care and effort should have a spirit of its own (or gain one though prolonged use as in the Japanese tradition of tsukumogami). A sapient inhabitant could potentially lead to a very dangerous weapon indeed.
Examples by type:
- Elric's sword Stormbringer from the eponymous novels by Moorcock. Significant Type 1 properties plus the ability to consume the souls of its victims and provide the wielder with buffs … and bad advice (being both sapient and "a thousand times more evil than thou").
Game and Story Use
- The prevalence of these things will vary immensely by campaign setting and rules system - the stock fantasy common to "certain fRPG systems" will be awash with them, whilst in a wainscot fantasy or low magic campaign, tracking down even one enchanted blade to take on an opponent immune to mortal weaponry may be a sub-quest in its own right.
- Interim measures include wainscot fantasy wherein an Enchanted Dagger of Blahblabla happens to be available on overnight shipping via your local new age curio shop (Mr Wheedon, please call your office) or where a temporary fix can be created using appropriate ritual magic.
- Prevalence will also have a bearing on value - if every man and his dog has a +1 sword, then enchanted weapons will need to be a very big deal indeed to be remarkable. If you actually need to lay hands on Kusanagi or Durendal to get a magical weapon, much less so.
- The Indonesian tradition is also something of a compromise - a strong strain of animism in their culture makes it not uncommon for a kris to possess special powers, depending on the nature of the spirit of the blade.
- A sapient, bloodthirsty sword capable of influencing its user is alarming enough … now imagine that same spirit inhabiting a handgun and turned loose in the black market of a major city… especially if it can also spawn its own ammunition1.