Undead Nature. The Wall doesn't require air, food, drink, or sleep.

Turn Resistance. The Wall has advantage on saving throws against any effect that turns undead.

Release Undead. The Wall loses 1d6 zombies from its mass every round, releasing them unto the world. If the wall reaches zero hp or if 5 rounds have passed, the wall falls apart and loses all of its undead. Releasing 1d6 zombies and 1d4 greater zombies.

Multi-Attack. The Wall makes 1d6 slash attacks from the arms of it's hoard.

Slash. Melee Weapon Attack: +3 to hit, reach 5 ft., 1 target. Hit: 6 (1d8 + 3) slashing damage.

Bite. Melee Weapon Attack: +3 to hit, reach 0 ft., all targets grappled by The Wall. Hit: 6 (1d6 + 3) piercing damage + 2 (1d4 + 2) necrotic damage.

Hoard of Wails. The wall screeches with its many voices. Each creature within 120 feet of the wall must succeed on a DC 18 Wisdom saving throw or become frightened for 1 minute. A creature can repeat the saving throw at the end of each of its turns, ending the effect on itself on a success. If a creature's saving throw is successful or the effect ends for it, the creature is immune to the wall's Frightful Presence for the next 24 hours.

Grapple. When The Wall succeeds on it's Slash attacks, it can grapple the targeted creatures as a bonus action. Target creatures must succeed on a DC 18 Strength or DC 16 Dexterity saving throw or be grappled. Grappled creatures may reroll the saving throw at the end of their next turn, breaking free on a success.

Bite. The Wall can make a bite attack to every creature grappled by it as a bonus action.

Slash. The Wall can make one slash attack to a creature within range as an opportunity attack.