Multiattack

The gug makes two slam attacks, two stomp attacks, or one of each.

Slam

Melee Weapon Attack: +11 to hit, reach 10 ft., one creature. Hit: 16 (2d8 + 7) bludgeoning damage. If a creature is hit by this attack twice in the same turn, the target must make a successful DC 19 Constitution saving throw or gain one level of exhaustion.

Stomp

Melee Weapon Attack. +11 to hit, reach 10 ft., one target. Hit: 20 (2d12 + 7) bludgeoning damage.