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Spirit Ally, Greater

(Oriental Adventures)

Conjuration (Calling) [see text]
Level: Shaman 8, Celestial 8,
Target: Up to 24 HD worth of spirits, no two of which can be more than 30 ft. apart when they appear

As lesser spirit ally, except you may call a single spirit of up to 24 HD or a number of spirits of the same type whose HD total no more than 24.
The spirits agree to help you and request your return favor together.