Mutagen

Mutagens are a special type of elixir that temporarily transmogrify the subject's body and mind. Typically, only alchemists have the expertise to craft mutagens. A mutagen always conveys one or more beneficial effects (listed in the Benefit entry) and one or more detrimental effects (shown in the Drawback entry). Mutagens are polymorph effects, and a subsequent polymorph effect attempts to counteract an existing effect; the counteract check for a mutagen uses the item's level and a modifier equal to that level's DC – 10.