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.

Undead Nature: As an undead Zook doesnt need to eat drink sleep or breath, even tho he likes a big piece of meat.

Unholly Cleaver: Zook have on his hand the Unholly Cleaver magic item and while he is alive nobody can attune to this weapon whitout his concent, Zook can call the Unholly Cleaver to his hand no matter whatever he or the Unholly cleaver is, when that hapen the Unholly Cleaver materialize on his hand.

Aura of Rotten Onion and Garlic: On a range of 10 ft around Zook creatures that can smell have desadvantage on perception checks. 

Cooks Cleave: +8 to hit 4d8 slashing damage, hit creature must suceed a constitution saving throw or take 2d12 necrotic damage half as much on a success.

Bound to the Cleave: If the unholly cleaver is away from Zook it reapear on his hand on the start of his turn. 

Aura of Pure Stench (Recharge 5–6) : As an Action Zook can concentrate his Aura of Rotten Onion and Garlic into a pure stench that covers an area of 10ft centered on Zook, creatures on that area other than Zook have desadvantage on attack rolls, this aura holds up for 1 minute.in adiction creatures that start their turn on, or enter the aura must succeed a constitution saving throw DC 15 or take 1d8 poison damage.