Bloat Zombie

Undead Fortitude. If damage reduces the zombie to 0 hit points, it must make a Constitution saving throw with a DC of 5 + the damage taken, unless the damage is radiant or from a critical hit. On a success, the zombie drops to 1 hit point instead.

Bloat Swarms. When the Bloat Zombie reaches half it's health or lower, it releases any of the following effects

Swarm of Adders. all creatures within 5 feet of the bloat zombie must make a constitution saving throw DC.16 on a successful save the creature take 2d6 poison damage, on a failed save the creature is poisoned until their next turn and take 4d6 poison damage.

Insect plague. treat the area around the zombie as though the Insect Plague was cast on the area around the zombie.

Swarm of Rot Grubs. any creature within 10 feet must make a dexterity saving throw DC. 14 on a failed save the target is infested by 1d4 rot grubs. At the start of each of the target’s turns, the target takes 1d6 piercing damage per rot grub infesting it. Applying fire to the bite wound before the end of the target’s next turn deals 1 fire damage to the target and kills these rot grubs. After this time, these rot grubs are too far under the skin to be burned.

 

Slam. Melee Weapon Attack: +3 to hit, reach 5 ft., one target. Hit: 4 (1d6 + 1) bludgeoning damage.

Retch Bloat. Melee Attack: the bloat zombie targets one creature within 5 feet, the creature must make a contested strength check or be restrained until the creature succeeds the strength check. (The Bloat Zombie has a Strength modifier of +3) 
If the Bloat Zombie wins the strength contest it will retch some of the contents of it's bloat onto the restrained creature mimicking the affect of its bloat swarms. The creature cannot make a saving throw to avoid these affects.