Laeral's Invisible Blade

This spell is the result of Laeral modifying a spell created by one of her sisters, Alustriel's sword of stars. Laeral's spell creates an invisible, silent, long-sword-shaped construct of force that forms at the end of the round of casting and attacks a chosen target creature.

During casting, the caster decides if the blade will strike with her own THAC0 inflicting 2d4 points of damage plus 1 point for each level the caster currently possesses, or if the blade will strike at THAC0 7, inflicting only 2d4 points of damage per hit. The version chosen cannot be changed after the spell is cast. For purposes of determining what the invisible blade can hit, it is considered a +5 magical weapon, though it does not have any attack or damage bonus.

An invisible blade cannot be seen unless or until it is blooded or marked with some other substance. Onlookers see only a creature fighting apparently empty air. Contact with any detection spell, regardless of its normal function, causes an invisible blade to become clearly visible.

The blade's first blow is always made at THAC0 5, regardless of which version of the blade has been chosen. The blade strikes twice per round until the spell expires or the caster chooses a new target creature. Because a creature concentrating on detecting (and parrying) the blade can see disturbances in the air as the edges of the force move, the creature suffers no Armor Class penalty for not being able to see the blade. Only those within 10 feet of the blade can see the disturbances.

However, if the blade is fought in complete (or magical) darkness, the standard Armor Class penalties apply and the blade itself strikes at a THAC0 of 5.

An invisible blade flies at MV 21 (A), has AC -2, and has 22 hit points. It vanishes if destroyed by physical attacks. Magical attacks have no effect on it at all, save that a successful dispel magic or a properly worded limited wish or wish can make it vanish.

The magical blade fights by itself, and does not require the caster's attention once created, except when the caster desires the sword to switch targets. Every time a new creature is chosen, the caster cannot cast spells on the round in which that choice is made. The round must be spent concentrating on the blade and the new creature, which must be within spell range of and visible to the caster at the time the choice is made. An invisible blade can follow a being anywhere on the same plane, though long-distance teleportation causes the magic to expire before the pursuing sword reaches its target.

The material components of this spell are any metal-bladed weapon, which is consumed in the casting, and a clear rock crystal.

Notes: Restricted to the Seven Sisters, their apprentices, and select Harpers in the Forgotten Realms setting.