Burying Spirit

Powerful Build. The spirit counts as one size larger when determining its carrying capacity and the weight it can push, drag, or lift. 

Evasion. If the spirit is subjected to an effect that would require it to make a saving throw to take only half damage, it instead takes no damage if it succeeds, and only half damage if it fails.  

Pit Traps. Once per turn when the Burying Spirit burrows into or out of the ground made from loose earth or stone, the spirit can create a mound of soft, mushy dirt: a Pit Trap. It can use its action on any of its turns to hide in a Pit Trap that it touches. A creature must succeed on a DC 14 Wisdom(Perception) check to notice a hidden Pit Trap before walking upon it. When a creature walks upon a Pit Trap, the creature is affected by the spirit's Bury action as if the spirit used its action and touched the creature, and the Pit Trap becomes normal ground again. 

When it is encountered, the Burying Spirit happens to be surrounded by 1d4 Pit Traps already hidden in random locations on the ground within 30ft of it. 

Slam: Melee weapon attack, +3 to hit, reach 5ft, one target. Hit 3(1d4+1) bludgeoning damage.

Bury: The ground churns beneath one creature or object that the spirit touches which is in or on the ground. If the target is a creature, it must succeed on a DC 12 Dexterity saving throw or sink 2ft into the ground. 

A creature that sinks in this way is Restrained; if its head is still above the ground, it can attempt to escape as if it were grappled against a DC equal to 10 + X where X is every foot beneath the ground it has sunk. A creature that sinks beneath its arms can't make melee weapon attacks or use somatic components, and if it sinks entirely beneath the ground, it is buried until it escapes and has disadvantage on ability checks made to escape. While buried, the target must hold its breath or begin suffocating.