Multiattack

The berstuc makes three slam attacks and Absorbs once.

Slam

Melee Weapon Attack: +10 to hit, reach 5 ft., one target. Hit: 14 (2d8 + 5) bludgeoning damage and the target is grappled (escape DC 16).

Absorb

The berstuc draws a Medium or smaller creature it has grappled into its body. An absorbed creature is no longer grappled but is blinded and restrained, has total cover from attacks and other effects from outside the berstuc, and takes 14 (2d8 + 5) piercing damage plus 27 (5d10) poison damage at the start of each of the berstuc's turns. The berstuc can hold one absorbed creature at a time. If the berstuc takes 20 damage or more on a single turn from a creature inside it, the berstuc must succeed on a DC 17 Constitution saving throw or expel the absorbed creature, which falls prone within 5 feet of the berstuc. If the berstuc dies, an absorbed creature is no longer restrained and can escape from the corpse by using 5 feet of movement, exiting prone.