Gronk

The gronk, also called the hopping rock or stone frog, is a huge, squat beast with mighty legs, a booming croak and a spiked headplate. Ram-folk nomads of the neutral planes say gronk have been around for five of their generations, and occasionally hunt them just to keep numbers down; planewalkers have also spotted them on several prime worlds.

Gronk have no subtlety. Anything they see draws a thunderous croak and a hopping charge of up to 180 feet that ends in a crushing headplate blow (2-16 damage).

Nearly deaf, they get +4 to saves vs. sound-based attacks and spells and take only half damage when they fail. Flashy lights madden them: some wizards toss dancing lights or pyrotechnics into a herd to send it into a frenzy, and the gronk turn on each other until almost none are left.

Gronk loathe even their own kind. A fresh herd lasts nearly a week before tempers fray and furious head-butting begins; it breaks apart and new herds form months later, so gronk may be met alone or in groups depending on this 'hate cycle.' Herds roam deserts, plains, mountains and swamps in nearly any climate but avoid oceans, lakes and other big water. Ram-folk thin them with coming-of-age hunts, which helps keep their numbers flat.

Their spite is how they reproduce. Reproductive organs lie near the brain in the forehead carapace, and the ridges there are 'buds.' A hard collision passes buds between gronk, and a new ridge grows within days, later dropping or being knocked off in another impact. If it lands on soil, sand or rock, it sinks a few inches and months afterward a tiny gronk burrows out. No one has seen a gronk eat. They live three to five years until the headplate cracks and flakes away and the brain fails.

Headplates make shields, armor plating, siege tower covers and shield walls. A gronk shield adds -1 AC against crushing attacks on top of the normal shield bonus but weighs over 50 pounds; users with Strength below 15 take -1 on Dexterity checks and attack rolls. A ram-folk tale tells of plates fixed to an enchanted ram that acted as a horn of blasting against structures but needed twice the usual bearers.

Bladderlike glands along the neck and upper back can be carefully removed, treated with resins and filled with acid to make grenades that work extremely well against fiends. Patrols in the endless war between demons and devils sometimes round up herds and pen them in the Lower Planes for harvest.