Ice Slick

You create a blast of intense cold, coating all solid surfaces in the area with a thin coating of ice. Any creature in the area when the spell is cast takes 1d6 points of cold damage + 1 point per caster level (maximum +10) and falls prone; creatures that succeed at a Reflex save take half damage and don't fall prone. Spell resistance applies to this initial effect.

A creature can walk within or through the area of ice at half its normal speed with a successful DC 10 Acrobatics check. Failure by 4 or less means the creature can't move that round (and must succeed at a Reflex save or fall); failure by 5 or more means it falls. Creatures that do not move on their turn do not need to attempt this check.

A 5-foot square of ice has hardness 0 and 3 hit points. The ice is an instantaneous effect, but persists as nonmagical ice. Under temperate conditions, the ice lasts 1 minute per level. In tropical environments, it might last only half as long. In cold environments where ice and snow persist without melting, it could last indefinitely.