"The undead require very little maintenance and rarely demand a salary or benefits. What they lack in speed and agility they more than make up for in persistence and can-do attitude. You won't hear any sass or whining from the undead! Since the victims themselves are transformed into walking undead, these henchmen are a smart investment that will grow your organization even when you are busy with other tasks."
The standard mooks in Hellsing. If a vampire sucks the blood of a virgin, they become another vampire; if they suck the blood of a non-virgin, they become a mindless ghoul who serves their creator.
More than that, anyone bitten by a ghoul invariably becomes a ghoul him/herself. Though the Millennium vampires' bite create ghouls whether the victim was or not a virgin. It's implied that this is because the process that makes them undead isn't as good as the proper way.
Likely intentional. They did make the ghouls able to function after the "parent" vampire's death. Accidentally creating a vampire that could act against them would not be very practical either.
An army of zombies had overrun a town in Princess Resurrection from a single zombie getting released and it turns out that the reason why Hiro is Hime's only blood warrior. A similar tactic was used against her in the past and it wiped out all of her vassals, including a group of her blood warriors. It takes a full-grown phoenix to put a stop on their rampage.
Turning characters who are dead (at the time anyway) into undead minions is an old comic book cliche, most recently seen in Blackest Night. Often leads to (at least some of) them being brought back to life fully.
On the Plains of Death in With Strings Attached, stepping on a certain part of the Plains (and triggered by an angry Jeft) causes endless ranks of skeletons, zombies, ghouls, and ghasts to rise up from the ground and attack. Oh, and the wraiths.
Inner Demons: Necromancy is one of the new skills Twilight Sparkle picks up after her Face-Heel Turn, and she quickly puts it to use, creating an army of zombie pony warriors to serve her.
Interestingly, these zombies have sentience and some degree of free will — they can talk, and at one point, two of them are seen arguing over the best way to carry out an order.
Films — Animated
The Cauldron Born in The Black Cauldron are an army of unstoppable skeletal warriors, mindless automatons serving their summoner the Horned King, who wants to use them to conquer the world. They can expand their ranks by devouring living people whole, and can be stopped only by undoing the Cauldron's spell.
Films — Live-Action
Army of Darkness features, well, an army of these that Ash accidentally released unto the world when he takes the Necronomicon without doing the chant properly.
Somewhat averted in Pirates of the Caribbean, where the undead crew of the Black Pearl still possess the sentience and free will that they had in life. They just happen to turn into walking corpses in the moonlight and can't gain pleasure from the world; not only that but it's said that these are their true nature and not the opposite.
In The Black Cauldron, the cauldron of the title reanimates corpses, and the enemy is using it for an inexhaustible supply of soldiers.
In The Dresden Files, Harry Dresden once had to deal with six necromancers coming to town at once. While only one (Grevane) made really copious use of zombies against Harry, since Dresdenverse zombies are more likeThe Terminator than anything, they were more than sufficient.
It turns out Harry really doesn't like people who use zombies, first because he considers it beyond the pale, and second because he doesn't really have a fall-back defensive ability when fighting them. For example, the defensive wards on his apartment will kill anyone that attempts to enter without fail. However, he did not anticipate a lot of people willing to sacrifice themselves to gain entry, or rather, someone controlling a lot of undead people that he was willing to sacrifice to breach the wards.
Chloe from Darkest Powers has the ability to create an army of the dead almost effortlessly, but since the process involves taking the spirits of people and shoving them back in their rotting corpses, she understandably tries to avoid summoning zombies as much as possible.
In the Laundryverse, zombies are more like low-class Eldritch Abominations that are summoned into deceased bodies. As such, they can be controlled—the more benign varieties, that is. Other types manifest as beings made of electric energy inhabiting stolen bodies, and skin is conductive. Special mention goes to the climax of The Fuller Memorandum, where Bob triggers one of these to seriously screw up a summoning ritual by cultists where he himself is to be the victim. The best moment goes to when he arranges for himself to be bound into his own body.
The Zombie Survival Guide recounts several experiments by the Imperial Japanese, Russians and Chinese to try to train zombies to create their own undead army. They did not end well. AT ALL.
Towards the end of the novel The Keep, a nasty Eldritch Abomination who pretends to merely be a vampire uses a group of German soldiers that it has killed to wipe out the rest of the German outpost.
Galaxy of Fear: City of the Dead features a mad scientist trying to create zombie soldiers. It goes right - not even horribly so, these zombies follow his orders, are not infectious, and are very strong, though how smart and dextrous they are depends on how long they were dead before he applied the serum. He also injects himself before someone can kill him, and comes back with his intellect and memories intact. However, an Undead Child he killed and quickly converted retains enough original personality to resist him.
Season 3 final in Merlin: all soldiers are turned into something closer to zombie invasion than regular soldiers. Being killed only by Excalibur, they definitely count as undead.
The undead often show up in games built on the D&D rules, where they have a host of special rules. They're immune to mind-affecting spells (preventing many of the better spells from working), immune to death magic, (preventing the best spells from working), immune to sneak attacks (making the Rogue more or less useless), and to top it off, skeletons resist piercing damage since there's nothing to pierce.
4th edition removes all of these restrictions. Undead now simply have resistance to one specific type of damage. Sneak attacks work just fine on them, and there's no longer any such thing as "mind-affecting spells", "death magic", or "piercing damage".
On the other hand, the two "holy" classes (Clerics and Paladins) can mow through them with ease - both get spells and abilities whose sole purpose is to kick undead hiney.
An old DM observation goes: "The number of undead encounters in a campaign is exponentially disproportional to the number of clerics in the party."
The Undead are immune to normal mind-control, but there is a Necromancy spell called "Control Undead". However, since it only works on the Undead few Wizards/Sorcerers bother to take it unless they know ahead of time that they will be encountering a lot of Undead. Same goes for the spell "Undeath to Death", which is the only way to bypass their immunity to Death magic.
Untrue! All the good undead creation spells are high-level/create standard zombies/skeletons. If necromancers want decent undead horrors at their beck and call, they have to go out and "catch" them. Being a necromancer is a lot like being a Pokemon trainer...
Subverted by Van Richten's Guide to the Walking Dead, a Ravenloft supplement which helps Game Masters equip ordinary zombies, skeletons, and other corporeal undead with an un-Mookish diversity of powers.
Pathfinder, being based on D&D rules, keeps the undead's immunity to certain spells, but removes the immunity to sneak attacks from corporeal (solid) undead. Ghosts keep it by function of not having a working anatomy.
Given the prevalence of Deathlords, the Abyssals, and shadowlands, zombies are common in Exalted. To aid matters, the Midnight Caste of the Abyssals have the ability to raise a corpse as a zombie with a touch, and there are several necromancy spells that raise anything dead as a zombie.
The Dry Bones (undead Koopas) and Boos from Super Mario Bros. 3. Super Mario World added undead versions of Buzzy Beetles and Cheep-Cheeps, as well as several new types of ghosts (Eeries, Fishin' Boos, Big Boos, etc.).
The ReDeads (zombies), Stalfos (skeletons), Gibdo (mummies), and Poes (ghosts) of The Legend of Zelda.
Marathon 2: Durandal was supposed to have an ancient S'pht bioweapon which turned Pfhor into Fungal Zombies, but it cut from the game because while it sounded really cool, a weapon that turns your enemies into uncontrollable zombies instead of simply killing them doesn't make much sense.
The Game ModMarathon Fell did have Pfhor who were zombified with a similar bio-weapon in its later levels.
And to make it worse, in the second game, the undead she summons are Made of Explodium.
Metal Slug 3 has quite a bit of these: You have to deal with zombified civilians and soldiers in mission 3, and later on you fight off legions of zombified clones of your previous player character while trying to escape from an exploding spaceship. You can even become a zombie and vomit acidic blood that can take out damn near anything in one shot.
The zombies in Nox who don't die unless you deliver the final blow with a fire-enchanted weapon or a fire spell and regenerate to full health otherwise.
In Warcraft III the Scourge are a faction of undead ruled over by a group of elite Death Knights and Liches who serve the Lich King. Whatever their magical plague can't convert into an undead zombie, they kill and reanimate with necromancy.
In the Frozen Throne expansion a faction of the Scourge splintered off. While they aren't above creating mindless minions to serve them, they generally don't go around converting everyone they kill. Then again, that changes in the Cataclysm expansion.
In World of Warcraft the Scourge's method of converting the fallen become increasingly evident. An army of undead elves, the San'layn, was created from those Arthas killed at the end of Warcraft III's expansion.
Oddly it's also become decreasingly effective, as much of Northrend is free of the Undead Scourge in part or in whole, and they seem to have lost that handy ability to raise significant numbers of the Dead, instead favoring the still-not-very-effective plague.
This is hinted to be somewhat intended. The Lich King himself, and some of his more intelligent minions, do have this power, and are shown executing it in certain places throughout the expansion, but the fact that they don't is played up as Arthas' human side showing some restraint.
The Death Knight class has the power to raise an army of ghouls to assist in combat.
The skeleton in level 3 of the original Prince of Persia is unkillable. The only way to get rid of it (and finish the level) is to keep pushing it back into a very deep pit. The skeletons in the sequel Prince of Persia 2: The Shadow and the Flame are also unkillable, but after beating them they fall to the ground, then rise again shortly afterwards.
The zombies in Quake cannot be killed by conventional means, as they rise again after a few seconds. The only way to get rid of them permanently is to destroy their body completely using grenades or rockets (cue Ludicrous Gibs).
"Thou canst not kill that which doth not live, but you can blow it into chunky kibbles" :)
In City of Villains, a Mastermind player character with the Necromancy powerset gets their own set of undead mooks.
There are also two enemy factions in City of Heroes - the Vazhilok and the Banished Pantheon - that are almost entirely made up of undead mooks.
And come Halloween, Holiday Mode ensures the city is overrun with zombies, ghosts, witches and werewolves...
The Hell chapters of The Darkness are filled with zombified souls of soldiers consumed by the titular quasi-demonic entity during World War One. Particularly horrible as the Brits cannot die no matter how badly their bodies are mutilated. Fortunately, the Narm of an arm-less, leg-less face-less moper in the village hospital cheers things up a bit. ...what?
The German zombie soldiers are the mooks, obviously.
Every so often, Left 4 Dead will send a massive horde of zombies at you. Unfortunately, the timing and the location of the Mook Maker are more-or-less randomized, so one never knows precisely when a pack of them will come running around the corner.
Call of Duty: World at War features Zombie mode. You and some friends vs. hordes of zombie Nazis.
The zombies in Eternal Darkness. Range from Mantorok zombies (who catch fire) to Xel'lotath zombies (who take "phantom limb" to whole-new levels) to Chattur'gha zombies (who regenerate) to Ulyaoth zombies (who explode).
Overlord features an area infested with zombies, as a mysterious and agonizing plague turns its victims into the living dead. In a twist keeping with its tone and sense of humor, it's caused by the proximity of a slutty, disease-ridden Succubus Queen; apparently, what's a harmless STD to a demoness is a virulent Zombie Apocalypse-inducing epidemic for humans.
In the sequel, people "infected" by magic are exiled to the Wastelands, an area devastated by a Class 0 magical detonation following the protagonist's disappearance in the first game. The exiles are transformed into mutated zombies by their close proximity to the overwhelming amounts of concentrated magic.
The normal enemies in the Siren series are all Undead Mooks called Shibito ("dead person" or "corpse"). They get more monstrous as time passes from their conversion... and simply can't be killed — they can be put out of action for a while, but the red water in their bodies will revive them. Generally, it's best to save resources and energy by sneaking past them instead of fighting them.
The newest installment, Wolfenstein, has the Despoiled, dead Nazis brought back to life as superpowered zombie monsters by the Elite Guards' dark magic.
Various kinds of undead are a staple of the Wizardry games, though they tend to only be common in certain areas.
In the fifth stage of the Touhou game Subterranean Animism, the player is introduced to Orin's army of zombie fairies. Shooting them down will only result in them coming back to life and then trailing after you, spewing bullets in their wake. It's one of the many reasons why that stage isn't very liked.
In Command & Conquer 3: Kane's Wrath, the Nod vanilla faction is given the support power, redemption. For a limited time, every militant squad (Basic Nod Mooks, weakest infantry in the game) killed in a certain area will be resurrected as a squad of Awakened (Zombie cyborgs). It's really more of a Useless Useful Spell, because militants are useless, and Awakened aren't all that much better.
EarthBound: Zombie Mooks are used by Master Belch to overrun the city of Threed. And they come in two flavors: Urban Zombies and Rural Zombies.
MOTHER 3 has zombies in the early part of Chapter 2, too.
Madworld had a zombie stage. The zombies were your everyday Mooks, but out of ALL the ways you could kill them, giving them horizontal cuts kept them alive. Though, when grabbed by a zombie in the first arena, Death would come in and give you five seconds to escape the zombie's grip, less you get an automatic death.
In Guild Wars the Necromancer class has the ability to raise and control a small undead army.
The backstory of the original game reveals that the entire nation of Orr was destroyed in a magical Class 0 event. The bodies that weren't instantly incinerated have transformed into an undead army that plagues the swamps of nearby Kryta. They are ruled by a Lich who caused said catastrophe and who you were helping all along.
And for Guild Wars 2, Orr will be raised from the ocean where it sunk after the catastrophe... by an evil dragon who turns all the corpses still there (plus the corpses of all sailors and pirates that happened to be around at the time) into undead Lovecraftian mooks. Orr just can't get a break, can it?
The Husks from the Mass Effect series are essentially cyber-zombies created by impaling people on spikes called Dragon's Teeth. The spikes inject them with nanites that convert parts of their tissue into inorganic matter. The Thorian Creepers from the first game look even more like traditional zombies, but they're some variety of grown, mutant clones that have never been real humans.
Shade Man's level in Mega Man 7 likewise features undead robots.
Metroid sports a few undead. The first undead appear in Super Metroid's sunken ship area: the boss, Phantoon, is apparently a ghost, and spectral clumps of skulls fade in throughout the level. Metroid Prime features Chozo Ghosts. And Metroid Fusion and Metroid Prime 2 contain human corpses reanimated by the X and the Ing, respectively.
In Hellgate: London, undead, and zombies in particular, are the weakest Mooks, but a zombie summoner could provide them in plenty. Some levels of the Necropolis can load one Necromancer every 5 feet, for a replenishing swarm that takes some work to wear down.
Dragon Age: Origins, with all the gorramed corpses you have to fight in Redcliffe. Undeath, in this setting, is usually reserved for spiritual manifestations (ghosts), not zombies. The Zombies in Redcliffe are corpses that have had demons implanted into them, making each type a slightly different fight.
Serious Sam: The various beheaded units, including the iconic Kamikazes, are all slain Sirian soldiers raised with an LCU (Life-Control Unit) and given either piss weak pistols with infinite ammo, a chainsaw, or grenades. As is appropriate for a fragile zombie with no armor, they are extremely weak. There's also the kleer skeletons, magically resurrected skeletons of some weird race◊ that look like a combination of horses and humans, with horns on their heads and scythes for hands. They are some of the most common enemies ever.
S.T.A.L.K.E.R. has former stalkers that have been made victims of rather unfortunate circumstances, from the Brain Scorcher, to Controllers, up to blowouts. These became a variation of a zombie in that they still have the brains to fire their weapons and even scavenge for loot, but they no longer became human due to their higher brain functions seared out by said circumstances. While they aren't that accurate in attacking and shamble about like sloths, they can still be dangerous to unsuspecting stalkers, especially in numbers. Otherwise, life proceeds on in the Zone, as it usually does.
To elaborate, the zombies are shortsighted, inaccurate, slow, and a bit dim, shambling towards you without using cover and firing from the hip if they manage to spot you (and you can stay out of their lines of sight, letting you put a silenced shot in their head and take them down in one hit) but they're also surprisingly resilient, taking quite a bit of ammo to put down if you don't go for a headshot. Also, the first time you'll encounter them in the first game, you'll most likely be coming out of an anomaly-filled tunnel on a surprisingly easy escort mission, when you see a guy standing off to the side of the road that at a glance looks like any other Loner. You'll probably get close to talk to him - and then he opens fire with a double-barrel.
Although not technically undead, the radiation-seared Feral Ghouls in the Fallout series, who have lost their higher brain functions due to degeneration, look and behave like fast zombies and reside in dark underground areas. Dead Money's primary enemies are the gas-masked Ghost People, who, like Hollywood zombies, continually revive unless decapitated. Old World Blues has skeletons in Animated Armor, and Lobotomites, who are cyber-zombies that have had their brains replaced with Tesla coils.
In Looking for Group, the undead sorcerer Richard mentions that he is the mayor of a little town on the coast. When he has to save his village from the legion and missionaries, it's eventually revealed that the entire town are undead as well; the villagers tear apart the legion fairly easily. They're actually fairly normal, except that the toddlers can tear out a man's heart barehanded.