Dispersed Focus. He can concentrate on a spell as long as he or one of the water clones is touching it or one of the creatures that are being affected by the spell.

Innate Spellcasting. Zabuza's spellcasting ability is Charisma (spell save DC 15). It can innately cast the following spells, requiring only verbal and somatic components:

At will: Shape Water, Create or Destroy Water, Create Food and Water (only water is created but double the normal amount).

50 charges (fully recharges every long rest): Fog cloud (1 charge), Zephyr Strike (5 charges), Blindness/Deafness (3 charges), Misty Step (2 charges), Mirror Image (5 charges), Tidal Wave (6 charges), Wall of Water (6 charges), Water Breathing (only as a ritual no charges), Water Walk (only as a ritual no charges and while the spell is active can choose whether or not to sink no action required), Control Water (8 charges) and Watery Sphere (6 Charges).

Magic Weapons. Kubikiribocho is a magic weapon.

Blindsight. While not deaf Zabuza has 30ft of blindsight.

Sneak Attack. Once per turn, he can deal an extra 2d6 damage to one creature you hit with an attack if he has advantage on the attack roll.

Cunning Action. He can use a bonus action to hide if obscured by fog.

Multiuatack. Zabuza attacks two times with Kubikiribocho.

Kubikiribocho. Melee Weapon Attack: +8 to hit, reach 10 ft., 1 target. Hit: (3d6+6) slashing damage. If there are two enemies in a straight 10 ft line within five feet of him when he hits he can use both of his attacks to hit both of them. If he misses his first attack he can use his second attack to shove the person back 10 ft with an athletics check making them prone.

Water Clone (5 charges). Zabuza creates a clone out of the water which can concentrate in spells for him, the clone has its own turn and rolls initiative. It can only make one Kubikiribocho attack which deals only 2d6 damage and can't cast spells, it has 20 hit points and regain 10 hit points at the start of their turn. And if need be treat all mental stats as +0 (10) and the physical the same as the original one they don't speak and receive mental orders while in the same plane. Zabuza can use the same bonus action to move and make the clones take an action. (AC 15)

Parry. Zabuza adds 5 to its AC against one attack that would hit him. To do so, Zabuza must see (blindsight) the attacker and be wielding a melee weapon.