There's a bit more to the lightsaber than your average long sword +1. As far as fictional technologies go, there's quite a bit to consider when translating this iconic weapon into D&D-esque terms. Not only are there numerous forms of sabers, there are a number of ways to alter their effects.
Essentially what we're looking at is an array of lightsaber types as well as rules for modifying their plasmic output.
An Aside: Power Consumption
A lightsaber gets its juice from a Diatium power cell that -- under the right conditions -- need never be replaced. However, like every good referee I can't resist putting limitations on this kind of thing. For example, what happens when PC the Jedi decides to slice his way through a dozen or so metal walls and barriers? You're telling me that a melee weapon can moonlight as a massively powerful drill for an extensive amount of time and not suffer any kind of adverse reaction? No no no no no no. There has to be a breaking point or the lightsaber becomes a little too useful, if you catch my drift.
Some Basic Lightsaber Types
- Standard: "The standard lightsaber consisted of a straight hilt approximately 20 to 30 centimeters long. As it is the standard make, it has no defining features other than details on individual hilts, as each weapon is often self-fabricated by the wielder and customized to suit their specifications."
- Double-bladed: "Also referred to as saberstaffs and Sith lightsabers, double-bladed lightsabers consisted of a single hilt that projected a blade from both ends, resulting in a deadly staff-like weapon. Most saberstaff hilts were of increased length, as they usually consisted of two separate lightsabers connected at the pommels."
- Pike: "Resembling pole-arms in many respects, lightsaber pikes featured extremely long handles, up to two meters long, with a somewhat shorter and thicker lightsaber blade. The handle was machined from phrik alloy to prevent it from being cut in two, as the purpose of the weapon was to provide increased range in close combat." And what Gygaxian game would not have pole-arms?
- Shoto: "Essentially, a shoto was a short lightsaber. Featuring a shortened blade length and diminutive handle, it was basically a miniaturized lightsaber. Shoto's were usually used as the secondary weapon in dual-blade combat, as their smaller blade length resulted in a less intensive gyroscopic effect, making the weapon easier to handle. Shotos were also used a primary weapons by some duelists, most who did so being of diminutive size, making a full sized lightsaber impractical, though this is not always the case."
Adjusting the Saber's Output
- Length: Vader famously carried a dual-phase saber that could be adjusted to a maximum length of three meters. This is not a standard feature of most lightsabers and could potentially be a costly modification.
- Power: All sabers should be able to regulate how much juice they're putting out. A lower setting might do fine when it comes to severing an opponent's limbs, but in order to hack through thick metal obstructions (i.e. denser material) a higher setting would be necessary. What happens when PC the Jedi raises the power output on his laser-sword? I would imagine it would become harder to wield (modifiers to attack rolls) and of course would inflict more damage.
- Most sabers don't work in water.
- Certain exotic metals (Mandalorian iron, phrik, Sith alloys, cortosis, etc.) effectively block or negate sabers' plasmic energy.