Firesight. Can see through areas obscured by fire smoke and fog with o penalty.

Smoldering Death. When it dies its body crumbles into smoldering coals releasing a great plume of smoke that fills 15 ft. radius sphere centered on zombie's corpse and spreads around corners. Area is heavily obscured and difficult terrain. When creature enters area for first time on a turn or starts its turn there: 7 (2d6) poison (DC 14 Con half). Smoke lasts for 1 min or until a wind of moderate or greater speed (at least 10 miles per hr) disperses it.

Undead Fortitude. If damage reduces the zombie to 0 hp it must make a Con save with DC of 5+the damage taken unless the damage is radiant or from a critical hit. On a success the zombie drops to 1 hp instead.

Undead Nature. Doesn't require air food drink or sleep.