Undead Warrior

Skeleton.  If the Undead Warrior leans more towards being skeletal it gains +10 feet of movement.

Zombie. If the Undead Warrior leans closer to a Zombie it gains access to Undead Fortitude. 

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.

Martial Advantage. Once per turn, the Undead Warrior can deal an extra 3 (1d6) damage to a creature it hits with a weapon attack if that creature is within 5 feet of an ally of the Undead Warrior that isn’t incapacitated.

Scimitar. Melee Weapon Attack: +5 to hit, reach 5 ft., one target. Hit: 6 (1d6 + 3) slashing damage.