From publisher blurb: High Concept: Three simple templates to make stone golems a much more interesting and varied group of foes, useful both to match thematic elements of a specific encounter and to surprise PCs when they do something new and unforeseen! Diamond (+2 CR):Diamond golems are not only extremely durable, but are also covered in amazingly sharp edges and points, making their attacks more powerful than standard stone golems. They also lose the slow special ability common to stone golems. Lodestone (+1 CR): Lodestone golems have the natural magnetic attraction of the lodestone used in their creation replaced by an arcane attraction for all metal. Pumice (+0 CR): Pumice golems are most often used by native island cultures as fast-moving guardians to protect and hold bays and caves, though their light weight also makes them popular as unsleeping sentinels on merchant ships.