Polymorphic Ring (3.5e Equipment)
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The ring functions like the alter self spell, except that you change into another form of living creature. The new form may be any of the following types: aberration, animal, dragon, fey, giant, humanoid, magical beast, monstrous humanoid, ooze, plant, or vermin.
The ring itself looks like a normal titanium ring that has symbols of an ancient wizard language on it. The ring was created alongside the Animal Spirit Ring. Unlike its counterpart, it isn't self aware.
However, the person can only change into one type of creature (Unless the CL is 10, which allows up to two or three creature changes). This resets when it switches to a different user. When on the user, they can change into that one creature and back as a free action.
If they lose the ring when not in their true form, they are stuck as the creature. If they are killed, they will reverts to their original form, though they remain dead.
Weak/Moderate Transmutation;CL 4/10; Forge Ring, Polymorph; Cost 8,000 gp; Weight: 0.001 lbs. lb.; Market Price: 20,000 gp