Bestasom

The Bestasom is a powerful four-star Monster that appears in the New World, with a Leviathan-class variant appearing in the Old World's Flooded Forest. This variant, dubbed an Aquasom, is a five-star due to being more violent as well as having access to stunning electrical music further amplified by water.

The Bestasom is characterized by it's power to utilize Soundwaves in attacks, sometimes composing 'Songs' for multiple purposes.

Physiology
The Bestasom is a Fanged Wyvern that has some elements of Leviathan roots, indicating that the mainstream New World variant evolved from Aquasoms that swam their way to said area and never left, due to Elder Dragon migrations or because conditions were more favorable.

Small fins appear on their arms and rear legs, and a long tail ending in a structure similar to a guitar pick appears behind them. Across their back are 4 membranes organized in a similar pattern to an acoustic guitar.

Bestasoms don't chew, instead using crushing-based teeth to mash their prey into a pulp, swallowing them whole. Why they did not evolve carnivorous teeth was due to the fact they are also omnivores, feeding off plants when the situation calls for it.

To create more powerful concussive attacks, Bestasom's can inflate their necks akin to a frog to produce a powerful fog-horn noise. This was an evolution from their Aquasom ancestor's sonar, and produces a more punishing Stun effect with heavy knockback if blocked.

Fins originally made for swimming have thinned out and greened, appearing quite similar to weeds or other plant based material

Behavior
Bestasoms are ambush predators, despite being capable of chasing down targets, and lie in wait underneath the ground