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The spellcaster may transform one Small or Medium-size animal with no more than 2 HD into a darkenbeast.
A target with an Intelligence score of 5 or more gets a Will save to negate the effect; targets with Intelligence of 4 or less are automatically affected.
The spell can only be cast in darkness: at night, indoors, or underground.
Its effects last until the darkenbeast is slain or until exposure to sunlight (see above) dispels the transmutation.
The transmutation can also be dispelled by a dispel magic spell, although such an attempt would have to overcome the darkenbeast's spell resistance.
A sunbeam spell automatically dispels the transmutation without needing to overcome spell resistance.
If you are going to imprint another spell on the darkenbeast, you must cast that spell immediately after the create darkenbeast spell is over and pass a Spellcraft check (DC 12 + level of the spell being imprinted).
The imprinted spell has no effect; it merely goes "into" the darkenbeast.
Another spellcaster using detect magic for 1 round can determine whether a darkenbeast has a spell imprinted.
After 3 rounds, detect magic and a successful Spellcraft check (DC 15+ level of imprinted spell) can identify what spell a darkenbeast has imprinted on it.
A created darkenbeast is under the caster's direct telepathic command.
There is no limit to the number of darkenbeasts a sorcerer or wizard can command, but a spellcaster can only have a number of darkenbeasts with imprinted spells equal to her caster level.
Material Components: Dried wyvern's blood smeared upon the spell's target, and a black pearl worth at least 200 gp.