Zombies never sleep, and they are incapable of fatigue.
Zombies are impervious to pain and require no air to breathe.
They are thus immune to drugs, poisons, gases, extremes of temperature and pressure, high voltage electricity, suffocation, and drowning.
While not invulnerable to physical injury, zombies can suffer great damage to their bodies (including dismemberment) without being adversely affected. Dismembering the legs will render the zombie immobile, but the creature will still continue to subsist. Likewise, decapitation will incapacitate the body, but the head will still "live".
Zombies don’t possess any superhuman strength, nor do they have a night vision, a characteristic usually common to undead monsters.
“walk or die” has been replaced by “die and walk”. The most terrific aspect of the zombie is that it first appears as the casual shape of a typical civilian which mind has been sucked out and left empty. Zombies are terrific because instead of delicately sucking your blood as the vampire, they come in disguise and brutally tear you into pieces. The deactivation of a zombie's nervous system, caused by the curse or chemical and genetic alterations, has often been used to explain their very low mobility and rate of metabolism. The chemicals in the human hypothalamus acts as a stimulant for their metabolism, prolonging their not-quite-dead condition.
Craving for human flesh
Zombies created by voodoo tend to be harmless, and are often used as slaves by the witch doctors that have created them. In spite of its rather feeble intelligence, the hollywood zombie is a both intellectually and physically driven only by his all-consuming hunger for fresh human flesh. Why the dead are so hungry for living flesh is still unclear?. As a slightly potty researcher illustrates in Day of the Dead, the dead do not need to eat, they reach for live flesh even when they have no mouth or gullet, even when their stomachs have been removed. The impulse is part of their very fibre, a spiritual craving. They are dead, and death wants to consume life. It is an image of insatiable nihilism that is hard to resist. In Romero’s trilogy and sequels, the world has discovered that these zombies are particulary fond of human brains, requiring the chemicals in the hypothalamus for maintaining their existence.
Some cases of vampiric zombies have also been recorded.
Zombies are also known to locate easily their preys across walls and distance. Do they smell living flesh like our Ogre of the fairy folklore ?
Another deadly aspect of the zombie is their ability to rapidly spread their undead scourge, increasing their numbers to vast measures. The bite of a zombie will cause its victim to quickly grow sick and die (usually within 3 days), only to rise again as a zombie. There is no known cure for this virus. Excision and cauterization of the "bite-infected" area (e.g. - removing a hand or arm, etc.) has proven to be completely ineffective in halting a victim's metamorphosis into the Living Dead. The fact that the majority of the zombie movies arrived during the 80s during the height of the AIDS epidemic is difficult to overlook.
The zombie's strength level is at normal human-levels, but they are considerably slower that average humans, possessing poor agility and coordination. Most zombies have difficulty with simple mechanical objects and obstacles such as doorknobs, latches, stairs, and fences. When confronted individually, zombies appear rather weak, but the creature's true threat is revealed when they are encountered in huge numbers. These relentless legions of tireless, flesh-eating machines will assault you on every side and corner until you fall and there comes the lunch
How to destroy zombies
Zombies are highly susceptible to fire, burning these creatures is the most effective way of destroying them. Extreme amounts of electrical current will burn a zombie's flesh, thus consuming it in flames. Zombies can also be dispatched by causing extreme trauma to their brain. This can be accomplished by driving a bullet, a drill, a long knife, a hammer, or some other blunt object into the creature's skull.
If the traditional zombie was easily destroyed by exploding the head but stronger chemical formula makes them more difficult to obliterate. In Braindead, Peter Jackson pushes the concept to its extreme limit. All the bits of flesh remain alive: the top half of a head which has been sliced off by a spade spends the rest of the movie getting kicked around the polished and increasingly bloody floor, blinking wistfully at the goings-on; one character's torso is eaten away, but the rest of the body, connected to the head by its spinal column, still waddles around the room; another zombie, cut in half, spills its guts onto the floor, and those guts then proceed to take on a homicidal life of their own.
The proper incantation and treatment of a the zombie artefacts such as the voodoo doll can harm the zombie and even destroy it. He can also be put to final rest through the appropriate voodoo ceremony, which forces the loa from its body. When a zombie tastes either salt or meat, he recovers his past personality and becomes aware of his state, immediately returning to the grave.