Sunlight Sensitivity. While in sunlight, the kobold has disadvantage on attack rolls, as well as on Wisdom (Perception) checks that rely on sight.

Pack Tactics. The kobold has advantage on an attack roll against a creature if at least one of the kobold's allies is within 5 feet of the creature and the ally isn't incapacitated.

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.

Dagger. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 4 (1d4 + 2) piercing damage.

Bite: Melee Weapon Attack: +3 to hit, reach 5 ft., one creature. Hit: (1d6 + STR) piercing damage

Infect: Bonus action: If the target is hit by the bite attack, the target must succeed on a 12 Constitution save. On a failed save, the target takes 2d6 necrotic damage and suffers from the poisoned condition. The target can reroll the Constitution save at the end of each turn to end the condition.

Zombie goop Throw Goo. (1/Day) The zombie hurls a ball of infectious goo that explodes at a point it can see within 30 feet. Each creature in a 10-foot radius sphere centered on that point must make a  DC 15 Dexterity saving throw. A creature takes 1d6 poison damage and 1d6 necrotic damage on a failed save or half as much damage on a successful one.