Algoids often resemble green humanoids, though they can just as easily take the appearance of a mound of green sludge or even spread out to blend into a scum-covered pool. The creature is not one being; it is an intelligent colony of algae awakened through some means. Usually this is through a magical accident, though some scholars believe an overuse of magic in fragile natural settings can cause an algoid to form. Others say the algoid is a natural magical expression tied to marshes and swamps, and the ability of the algoid to "awaken" trees to join in the defense of its home lends some credence to this theory.