So, I made a couple of posts that were advertising. Time to offer a monster.I sketched a little picture of the Grumprock that's basically "before and after."
The grumprock is a creature of the elemental plane of earth, but they are encountered on the material planes more frequently than other elementals since they form as polyps on large rock formations, eventually breaking away and wandering about, although they never go fer from their parent rock formation. They resemble ordinary boulders when they are inactive, which is most of the time. However, if they are hungry or disturbed, the top of the grumprock opens to reveal the creature's interior, which is much like that of a mollusk. The grumprock's interior extrudes a very long, triple-tongue that it uses to grab its prey and smash them around until the shells are broken and the creature is dead. Each of the tongues attacks independently, and if it hits, it winds around the victim. Anyone entrapped in this way can attempt to break free each round by making a saving throw just after being smashed. Smashing begins on the round after the victim is enfolded in the tongue, and causes 1d6 points of damage automatically.
Grumprocks are always surrounded by a pungent smell, which is rust monster pheromones. Rust monsters are attracted to the grumpocks by this smell, enfolded in the tongue, smashed open, and eaten. The area around a grumprock may be marked by the smashed shells of rust monsters if the grumprock has remained in the same place for long enough.
Grumprock: HD 6; AC 0; Atk tongue (special); Move 3; Save 11; AL N; CL/XP 8/800; Special: tongue.