Appearing as an ordinary pointed hat, this magical device will radiate a dim dweomer of the evocation sort. 

Any magic-user possessing the item can cause its power to function by pointing the small end of the cone toward the ground and then tossing the cyclocone forward with a spinning motion imparted by opposite movement of the palms of the hands. When thus set in motion, the cone begins to rotate at blurring speed and grows into a miniature but exceptionally powerful whirlwind. 

This whirlwind is 5 feet wide at its base, 15 feet wide at its top, and as much as 45 feet high (depending upon ceiling height or some other such limiting factor), It appears within 1-4 segments after the cyclocone is cast forth. 

It sweeps ahead in a straight line at a movement rate of 18", proceeding for 1 full round or until a solid, sturdy object destroys it; a stone wall, very thick woods, etc., will cause it to break up. 

(Note that a living thing which serves to break up the whirlwind in this fashion will take damage as described below.) 

Any creatures of under 2 + 1 hit dice that are caught within the whirlwind when it forms or are touched by it along its movement path are instantly killed by the force and carried along by the whirlwind.

Other creatures caught within the whirlwind or touched by it will take 4-16 points of damage, and those within 5 feet of its outer edge when it forms will take 2-8 points of damage. 

The cyclocone is not reusable; the item is destroyed when the whirlwind is dissipated.