This spell can be cast upon any fixed point on the tabletop. If successfully cast, place a suitable marker over the exact spot affected - a small coin is ideal for this.
Once cast, the player rolls a D6 at the start of each player's turn (ie, at the start of his turn and at the start of his opponent's turn). On a score of 1-3 nothing happens, but place another marker on the first. On the score of a 4-6 the spot is struck by a comet. All units from either side which are within D6" multiplied by the number of markers already placed are struck by the comet. Each unit struck by the comet takes 2D6 Strength 4 hits. For example - if there are two markers in place and the D6 roll is a 4, all units within 4 x 2 = 8" are struck. The Comet is not aspell as such, although the spell can be dispelled while in play, (remove all markers), and a Wizard cannot have more than one Comet in play at one time.