[Michael Thayne]

This build really stretches the definition of "wall", but it seems to me the difference between "curtain of fire descends for a split second" and "fire blast hits everyone in its path over the course of a split second" is largely cosmetic. Substitute "crushing damage from air magic" for "fire" and you get this spell. +0% struck me as reasonable for the random twisting because it's like Wall, Shapeable (which costs 30% more than a regular Wall) only you don't control it.

Twisting Terror
Keywords: Area (Special).
Full Cost: 22 points for level 1 + 5 points/additional level.
Casting Roll: None. Use Innate Attack (Gaze) to aim.
Range: 100 yards.
Duration: Instantaneous.

Conjures a small tornado that rips across the ground, smashing everything in its way. The caster must choose a starting point (calculate distance penalties from that point). The twister appears there and cuts a swath one yard wide by three yards high. To find total distance travelled, look up the level of the spell on the Leveled Area Table (GURPS Thaumatology: Sorcery, p. 9) and read "radius" as "distance". The caster does not control the path – each yard, roll for Scatter (p. B414) to determine the direction moved.

Anyone the tornado would touch may attempt to dive for cover (p. B377) to get out of its path. Other active defenses are ineffective. Success means that person ends up on the ground, unharmed. The tornado can sweep over a victim repeatedly, doing damage with each pass. If that happens, diving for cover is useful just once.

Those who fail to get out of the way are pummeled with a 2d crushing attack; this is large-area injury (p. B400). Use double damage to calculate the amount of knockback, and Scatter to determine its direction.

Needless to say, this spell is best cast at a safe distance from the caster and any allies!

Statistics: Crushing Attack 2d (Area Effect, 2 yards, +50%; Double Knockback, +20%; No Signature, +20%; Persistent, +40%; Nuisance Effect, 1 second duration becomes instantaneous, -5%; Reduced Duration, 1 second, -20%; Sorcery, -15%; Wall, Permeable, +30%; Wall snakes randomly, +0%) [22]. As a special effect, those in the path of the twister are hit in quick succession rather than all at once. Additional levels add Area Effect (+50%) [+5]. This spell originally appeared in GURPS Magic: Artillery Spells, p. 10.