Magma and Ice Trolls

From publisher blurb: Not technically trolls, magma and ice trolls are called such for the similarities in their appearances as well as their ability to regenerate. More generally, adventurers like to refer to them as "elemental trolls", though there are no records of such creatures existing with alignments toward electricity or acid. This Monthly Monster provides all the lore, tactics, and stats you need to run it in your game, and provides an elemental take on the classic troll concept.