The undead, or zombies as they are more commonly called in popular culture, but only rarely referred to as such in Undead Nightmare are, by definition, a type of living being that has either died and been reanimated by the means of a curse, magic, science, or an infectious virus, or remains living but has lost higher mental functions due to any of the aforementioned reasons. This incarnation of zombie spawned when Abraham Reyes discovered an ancient Aztec Mask under the bull fighting ring in Escalera. He took it, thinking that it would grant him invincibility and immortality, but instead it turned him into one of the Undead as well as resurrected the dead as far as New Austin and West Elizabeth. The Undead will generally swarm and attack the closest living thing they can get their hands on. They seem to be attracted to sound and fast movement as they are quickly able to determine the location of a discharging firearm.
The Undead will rarely attack one another, but there are exceptions. When playing as Zombie Marston during the single player campaign, the Undead will often ignore the player completely or slowly approach the player in a non-threatening manner, almost as if it is curious (this only applies to Undead humans). Upon getting in arms reach, they will attack but will not sprint and give chase if the player attempts to escape. Sprinting around them will quickly draw more attention to yourself so it is recommended to walk when in their direct presence. Any violent action done in their presence will send them into a frenzy and make them attack the player as they did before the player became undead. Interestingly, undead animals such as wolves will often prioritize a living mount over the undead player and will chase it for quite some time but they will still attack you if on foot.
The Undead are extremely difficult to kill due to the fact that they are in the limbo between the world of the living and the world of the dead. They can only be killed by destroying or severing the head, burning them with the Torch or War mount, cleansing them with holy water, drowning them, destroying the body itself with an explosive or with the Blunderbuss, or ramming them with the Death mount (causing their heads to explode). They act in a primal, savage manner, feasting on the flesh and blood of the living to try and satisfy their seemingly insatiable hunger. The Undead look rotten and decayed, some having exposed bone sticking out of their sickly green to pale gray skin, others missing eyes, ears, teeth, and even whole pieces of flesh. When an Undead bites a living creature, it becomes "infected" with whatever it is causing the dead to come back to life, having only a few seconds before dying and joining the ranks of the Undead Horde. Some Undead seem to have some recollection of who they once were, saying things they had when were alive, as seen in the case of some Boss Undead. The things they say, however, are in an eerie, distorted, almost unrecognizable voice. In one case, a zombie prostitute can be seen offering her services to a zombie male.
However, it seems that if a person is resurrected from the dead while in possession of a bottle of Holy Water (or presumably anything blessed or holy), they will be resurrected with the rotted body of an Undead, but with the soul and mind of who they were, thus meaning that they mentally are that person, as with the case of John Marston. It is unknown if there are any others of Zombie Marston's kind, but it is presumed that there are no others as none have been found, not even in a pastor's grave.
It is implied through conversation with Ayauhteotl that the undead are actually acting on their own accord and do not want to go back to being dead. Thus why the the mask must be returned to prevent them from rising from the grave once more.
Types of Undead
There are four different categories of undead found in the DLC, not counting undead animals.
Traditional undead are typical zombies, but actually quite fast corpses and will make up the bulk of the undead hordes. Along with Bolters, these zombies are the only kind that can grapple John, possibly because they hold no other special characteristics unlike the other types of undead. They are found mostly in massive hordes, and if they grab you off guard, they can seriously injure or even kill the player.
These are some notable characters that were turned into undead.
- Abigail Marston **
- Jack Marston **
- John Marston
- Nastas *
- Harold MacDougal *
- Lucille Billingsgate *
- Herbert Moon *
- Vincente de Santa
- Jimmy Saint
- D.S. MacKenna *
- Peter Turner
- Alma Horlick
- Moses Forth *
* - possibly cured if hogtied
** - cured
Bolters move about much more quickly by scampering on all fours, making them hard to target. Like Fresh Undead, Bolters can grapple Marston and potentially kill him. Their main attack is biting and clawing at the player in a rapid succession, making them extremely dangerous when in hordes. Bolters appear to be small, and frail looking, and they walk like they have a limp until they see you, ironically making them the slowest Zombie as well if they are on just their legs. They are usually easy to spot from a distance.
Bruisers are big, fat, and slow, with stamina above other zombie types making them tough to kill. They will also charge at the player from a distance to knock him down. They can be seen pretty easily when within a group of zombies. It is recommended to try and take them out first since they can knock down Marston quickly making him a meal for any nearby Bolters.
These are some notable characters that were turned into Bruisers:
- Retchers glow green, smell worse than other undead, spit toxic bile at the player, and explode when killed, causing damage to the player (it will stun the player if playing as undead John Marston) as well as any other Undead or NPCs caught in the blast. They can be found in and around Gaptooth Ridge and most of Nuevo Paraiso.
- With the exception of Retchers, all undead enemies are short-ranged, melee attackers, therefore the player will not have to take cover against them.
- The best way of avoiding Undead is to constantly outrun them and use Dead-Eye Targeting to get easy headshots on multiple zombies.
- The Bolters are the hardest to hit due to their fast speed, so try to save the majority of Dead-Eye for them. Also, zombies cannot climb over obstacles, and they will get stuck on fences, so try to put something between the player and them. Elevation also works to the player's advantage, as Undead cannot climb, so stay on the roofs of buildings.
- When suddenly attacked by a small number of undead, with no way to escape, it is unwise to waste time reaching for a melee weapon like your torch, as it is slow and will take a long time to kill the undead. Instead, pull the trigger while they are attacking the player and he will automatically hit them with the butt of his gun or perform an Execution, both of which are instant kills.
- This is also a valuable tactic when conserving ammo or on relatively small targets, like Bolters.
- Going inside buildings is one of the most dangerous things a player can do, especially if the player has more than one Undead to deal with. If the player does get stuck in a building, try to find an area that will funnel the zombies into a semi-straight line. Use Holy Water to destroy them group by group. If players don't have any Holy Water, get out the gun with the highest ammo capacity that the player has and use Dead-Eye to target and take them out.
- Players should choose their targets wisely. Using their valuable ammo to take out the more powerful Zombies first. The suggested order for a normal situation is BRUISERS - BOLTERS - RETCHERS - NORMAL. Retchers and Bolters can be interchanged depending on the situation. Also, Bruisers are more dangerous in cramped quarters, though Bolters should be priority.
- Reloading isn't something the player wants to do while being chased by a certain number of undead. Therefore, the player should (if the option is available) use Dead Eye quickly, and then turn it off. This way, players will approximately reload almost instantaneously.
- Rifle-butting a Bolter will always kill them, and they may even block the Undead behind them, buying the player some time.
- A good tactic when dealing with the undead is to outrun them, then press in the right stick to make John look behind him. Then, while holding down the right stick, press the aim button. This makes John do a quick 180 degree turn and then the player can go into dead eye and take care of the undead. This move also sets up easy executions for the undead that are chasing the player.
- When surrounded, find something to vault over. The Undead cannot climb, so vaulting over something - such as a railing, wall, etc. - will separate them from the player. They will have to find an opening to get to the player, and while they are doing that, the player can run away and heal.
- It is recommended to use Casual targeting mode, as using this makes the player to immediately point their gun at the head of the nearest Undead in their line of sight when aiming, making it an easy kill with a push of a button.
- However, using Normal targeting mode will still cause the player to always aim at the head of a Bolter, but just at the body of any other Undead variant. Due to this game mechanic, Bolters are perhaps the most easy type of Undead to kill
- Choosing the right weapon for fighting Undead requires a different approach than in the main game. Because Undead can only be killed with headshots, high-power weapons with small magazines and slow firing rates (particularly rifles, however the speed loader on the bolt action rifle makes it effective for medium distances and executions) are much less effective than in Red Dead Redemption. Since a single headshot will kill an Undead, regardless of the power of the weapon used, the importance of damage in weapon selection is minimal. Instead, the most desirable traits in a weapon are magazine size, rate of fire, and reload speed. This makes Repeaters and Pistols two of the most useful weapons to use when fighting the Undead. However, while on foot, Shotguns can be invaluable, since their spread makes it extremely easy to get a headshot on an Undead, and in tight groups can kill or knock down multiple Undead.
In Multiplayer, there are eight zombie player models, six of them being recycled Bolter models. They have exactly the same abilities as the normal characters. They also appear as enemy NPCs in the Undead Overrun gamemode.
The player cannot play a zombie character when joining an Undead Overrun gamemode, and it will automatically give the player a random character from the outfitter depending on what the other players' characters are.
- Walking around with a hogtied Retcher for too long will cause it to rupture, killing the player. This can be negated by setting them on a horse.
- Players may come across wandering civilians claiming to be sick and requiring a doctor. These troubled folk have been infected and, after a short while, will fall to the floor in pain, or vomit. After which, they'll attempt to attack the player. They can be recognized by their obvious pale skin. If the player momentarily lassos them before they turn, they will seem to be cured, though run off scared if not hogtied.
- If the aforementioned civilian is a lawman or is otherwise equipped with a firearm, he may open fire when lassoed or intimidated by the player with a firearm of their own. Be very careful around these victims of the undead plague, as they can catch the player off guard and kill them within seconds.
- Usually, after saving a town, the player will encounter a woman approaching an undead, thinking they are a previously deceased loved one that is still alive. The undead will try to infect the woman, and John can save the woman by shooting the undead, or hogtying it.
- Sometimes the Doctor from the "Doctor" Random Encounter can be heard saying: "I wish they didn't explode when they die. They'd make excellent test subjects!", implying that he wants to study Retchers. This is backed up by encounters in Gaptooth Ridge and Nuevo Paraíso, where he may request a Retcher specifically.
- The unusual types of undead (Bruiser, Bolter, Retcher) share a strong resemblance to the Special Infected of the popular zombie apocalypse game Left 4 Dead video game series (Charger, Hunter, and Spitter, respectively).
- Undead may retain some human qualities such as lust, as hinted in the opening for the survivor mission, "Biographies and Lies".
- When an NPC kills a Retcher, it may not explode. However, the player is still unable to loot the corpse.
- Killing a Retcher with Holy Water will also not cause it to explode.
- There is a Retcher character model within the game that bears a resemblance to Irish. It has similar grey pants, an olive green shirt, messy hair, and a full beard, similar to Irish.
- If the player walks near a Retcher, as soon as it ruptures, Marston will immediately start jogging.
- If being attacked by a group of undead, they may grapple John. If the player isn't careful, they can kill John instantly if caught off guard.
- Although all undead can die from a single headshot from the weakest of weapons, some undead can be seen with cleavers or tomahawks lodged in their heads.
- Undead may glitch and do civilian actions such as stealing a horse. However, they always get back off it after. They may also do other things that are human by accident.
- The fresh undead use the same models as many NPCs. However, they have been modified to appear undead, with the addition of pale skin and blood-soaked clothes.
- If the player spots a fresh undead from a relative distance away, the fresh undead may look just like their alive NPC counterpart. However, once the player gets closer, the fresh undead will look like a zombie.
- When mounted on a horse and standing still (or moving slowly) around a group of undead, they will approach the horse and pull the player off. They will proceed to attack the player, and occasionally attack and kill the player's mount.
- There is a rare texture bug where a zombie will appear as a regular, uninfected NPC.
- The Undead can still drown in water like any NPC or the Player would.
- Humorously, the player can taunt the Undead. For example, if one was hogtied and the player presses the action button, John may taunt the Undead with many insults, including asking if the zombie is Bill Williamson.
- The player can only taunt Fresh Undead and Retchers. They are unable to taunt Bolter and Bruiser undead.
- The player can "greet" Fresh Undead. Simply ride on horseback near a Fresh Undead, and tap the greet button (B on Xbox 360, Circle on Playstation 3). Marston will then tip his hat to the Fresh Undead next to him.
- The largest horde of undead that the player could possibly find is in Jorge's Gap, as the entire area is full of the undead.
- Note that there are two Zombie Ricketts zombies that can be encountered throughout the game, The first one is a Bolter which can be found anywhere outside of West Elizabeth, while his Retcher version can be found in Gaptooth Ridge and all over Nuevo Paraíso. Notable differences are the colors of their coats: The Bolter version has the same Cobalt Blue duster coat with little bloodstains on it while the Retcher version of him has a Green duster coat instead of his usual blue one, note that this one is also full with bloodstains.
- As of June 2014, an update occurred that has made Undead Nightmare unplayable for many players. The undead's heads will become invisible after about 10 or 15 minutes and, if the player tries to save, their game it will not save and they will have to restart the game. Also, any mythical creatures that the player find will have no saddle and will kick the player off. This can occur with both the digital copy of Undead Nightmare, and the Game Of The Year copy.
- In some trailers and promotional screenshots, Retchers were shown to appear in West Elizabeth. They cannot be found in this territory during actual gameplay.
- Bruisers and Bolters only appear in West Elizabeth during the mission Curious Tales from Blackwater. Bolters, however, are sometimes the undead chasing the man/woman during "The Zombie Prey" Random Encounter.
- During the "You only die twice" Random Encounter, the undead may appear without blood on their clothes or skin. They look very similar to their human counterparts, minus their pale skin.
- While headshots are the quickest and safest way to kill undead, it is possible to kill them with body shots, however this takes a significant amount of bullets.
- A strange glitch can happen when messing around with the Invulnerability Cheat. If you stand within a group of undead for long enough, one may attempt to grab and bite you, prompting a quick time event to escape. If you let the zombie succeed, you will not die after the bite animation is complete. The glitch is that the undead will no longer act hostile towards you. This glitch lasts for a seemingly random amount of time or until you reload a save.
- A possible glitch may occur where Undead females can be heard making chicken noises.