D&Dtools1

A globe of supernaturally dry air rolls in whichever direction you point and engulfs those it strikes.
It moves 30 feet per round and can leap up to 30 feet to strike a target.
If it enters a space with a creature, it stops moving for the round and deals 2d4 points of damage as it evaporates moisture from the target.
(The subject can negate this damage with a successful Reflex save).
Oozes, creatures composed of water (such as water elementals), and creatures with the aquatic subtype take 2d6 points of damage.
The bubble moves as long as you actively direct it (a move-equivalent action for you); otherwise, it merely stays at rest.
The surface of the bubble has a spongy, yielding consistency (similar to that of a soap bubble, but not fragile and allowing objects to pass through it without affecting the spell) and so does not cause damage except by absorbing moisture.
It cannot batter down large obstacles.
The bubble winks out if it exceeds the spell's range.
Arcane Material Component: A tiny bag or bladder filled with air, and a sprinkle of dust.