Multiattack

The dune mimic makes three Pseudopod attacks. It can replace one attack with a use of Engulf.

Pseudopod

Melee Weapon Attack: +8 to hit, reach 15 ft., one target. Hit: 18 (3d8 + 5) bludgeoning damage. If the dune mimic is in object or terrain form, the target is subjected to the mimic's Adhesive trait.

Engulf

The dune mimic engulfs a Large or smaller creature grappled by it. The engulfed target is blinded, restrained, and unable to breathe, and it must succeed on a DC 15 Constitution saving throw at the start of each of the mimic's turns or take 10 (3d6) slashing damage, as the creature is lacerated by the mimic's sand-coated form. If the mimic moves, any engulfed creatures move with it. The mimic can have no more than two creatures engulfed at a time.