Poison Drinker. The zombie is immune to poison damage. Any poison damage it would otherwise take is translated into restored hit points instead.

Drag Down. The zombie has advantage on attack rolls against a creature it is grappling. Furthermore, it has advantage on Athletics checks made to grapple, shove, or throw creatures if any other zombie is also within 5 ft. of the target.

Rotten Fist (Unarmed). Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 5 (1d4 + 3) bludgeoning damage. On hit, target must make a DC 12 STR saving throw or become grappled, with stacking Disadvantage on the saving throw for every other zombie with within 5 ft of the target.

Bloody Sickle. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 5 (1d4 + 3) slashing damage. On hit, target must make a DC 12 CON saving throw. On failure, the target takes 2 (1d4) piercing damage and starts to bleed. At the beginning of each of its turns, the target takes another 2 (1d4) piercing damage, then repeats the saving throw to end the Bleeding condition.

Zombie Bite. Melee Weapon Attack: +5 to hit, reach 5 ft., one grappled target. Hit: 6 (1d6 + 3) piercing damage and 7 (2d6) necrotic damage. Creatures slain by this attack rise from the dead as zombies (sharing the same stat block).

Lunge. As a bonus action, the zombie makes an additional unarmed melee attack against its target with a reach of 10 ft. On hit, the zombie moves closer to its target, and the target must succeed on a DC 12 STR saving throw or fall prone. On miss, the zombie falls prone instead.

Relentless Grab. As a bonus action, the zombie can attempt to grapple a creature within 5 ft. of it, and can do so even if it's prone.