(Drow of the Underdark)

Transmutation (Polymorph)
Level: Sorcerer 5, Wizard 5,
Components: V, S, Drow
Casting Time: 1 swift action
Range: Personal
Target: You
Duration: 1 round/level (D)

Your lower extremities transform, sprouting arachnid legs, as a large, pulsing thorax swells from your back.
You take on the form and abilities of a drider (MM 89).
You gain 20 temporary hit points, which disappear at the end of the spell's duration.
You don't gain the drider's spellcasting ability, but you retain your own.
(Spellcasting is subject to the drider's ability scores; for instance, you can't cast wizard spells above 5th level, since your new Intelligence is only 15).
Any held objects remain held in the new form (other gear melds into the new form as normal).
See page 59 for details of the polymorph subschool.