Ki. A Monk Skeleton has access to 8 ki. Ki is restored at the end of a long or short rest.

Fingers of Death. When a zombie monk successfully hits a target two times in a row, it can spend 3 ki points to deal with additional Xd6 necrotic damage, where X is equal to half of the target level rounded down.

Reactive Opportunist. When an enemy fails an attack roll against a zombie monk, it can spend 1 ki point to make an unarmed strike attack as a reaction.

Savage. When a zombie monk makes an unarmed attack roll, it can make another unarmed strike as a bonus action.

Expulsion Imunity. The zombie monk is immune to effects that banish undead. 

Legendary Resistance (3/Day). If the vampire fails a saving throw, it can choose to succeed instead.

Regeneration. The zombiemonk regains 20 hit points at the start of its turn if it has at least 1 hit point and isn't in sunlight. If the zombie monk takes radiant damage or damage from holy water, this trait doesn't function at the start of the monk's next turn. 

Sunlight Sensitivity. The zombie monk takes 10 radiant damage when it starts its turn in sunlight. While in sunlight, it has disadvantage on attack rolls and ability checks.

Multiattack. The zombie monk makes three attacks, or use Necrotic Pulse of Ki.

Unarmed Strike. Melee Weapon Attack: +9 to hit, reach 5 ft., one creature. Hit: 15 (2d8 + 4) bludgeoning damage. Instead of dealing damage, the zombie monk can grapple the target (escape DC 18).

Necrotic Pulse of Ki (2 Ki Points). Ranged Weapon Attack: +9 to hit, reach 30 ft., three creatures. Hit: 12 (1d8+4) necrotic damage. The targets must succeed on a DC 16 Constitution saving throw or will not be able to heal hit points until complete a short rest.

Deflect Missile. In response to being hit by a ranged weapon attack, the monk deflects the missile. The damage it takes from the attack is reduced by 1d10 + 5. If the damage is reduced to 0, the monk catches the missile if it's small enough to hold in one hand and the monk has a hand free.

Evasion. When you succeed on a Dexterity saving throw to halve damage, you take no damage instead.