Warcraft III - Undead

2-3 Heroes, Crypt Fiends, Statues/Destroyers
This is the most common army you will see. Undead players often go three Heroes.

Crypt Lord Beetles + Crypt Fiends
This is a good early game combo. The Carrion Beetles tank for the Crypt Fiends.

Mass Ghouls
Mass Ghouls can work well with Ghoul Frenzy and a Dread Lord and Death Knight with their Auras.

Necromancers
Necromancers are especially powerful in team games when other players can back you up.

Dark Ranger + Crypt Fiends - Player Submitted Strategy
This strategy is a very useful tactic early on, if the phrase 'micro-management' doesn't scare you. It works better in team games, but can also sometimes work in solo games. It can be a game ending tactic against inexperienced human players. To pull this off effectively, you need 2 Crypt Fiends. As soon as you have 2 Crypt Fiends and the Dark Ranger Hero from tavern, you can and should attack the enemy base. Preferably, look for a Human player, but it can also work against a Night Elf player going Archers. It can also work against an enemy Undead. Orcs players are usually too tough cause of burrows. The main focus of your attack should be to kill as many units as you can, regardless of their importance. This means that you should pick the low health units (usually that's going to be the workers) and ignore the fighting guys (especially melee). What you want to do is, invest the first skill point in Black Arrow (autocast) and get an army of skeletons ASAP. It’s best start with a small Creep camp next to enemy base. Focus fire on each Creep after another and let the skeletons tank for you. Once you have 3+ skeletons and at least 2 Crypt Fiends, attack enemy workers. Get in the base, avoid the possible Arcane Tower, and focus your fire on the workers (wood choppers first), as you did with the Creeps. Take them down one by one, ignoring enemy fire as long as you can afford it. Keep producing new Crypt Fiends (rally point set on Hero) and retreat your wounded ones. Research Carapace Improvement for your Crypt Fiends ASAP. Try to take down all the workers until your Hero gets low on health. Remember that every unit you kill with Black Arrow will raise one skeleton. Usually it's better to kill 2 Peasants and get 2 skeletons than to kill one footman. Some of your skeletons should keep the enemy army busy, while you continue to kill enemy workers. If your Hero hasn't died (along with your army) by the time you killed all workers, you may retreat for healing, leaving the skeletons to fight the enemy.

Humans are the perfect target for this assault. You can attack Orc players until they hide in burrows. When they do, you will not get skeletons. So it’s better to leave. Night Elves are a good target if they mass Archers, but if they go Huntresses, you'll be in some trouble. Undead work fine. Focus first on Acolytes and after that, on Ghouls (many inexperienced players won't even call the ghouls to fight. They'll just let them chop wood until those die). Always focus fire of your ranged units on the most injured enemy unit in vicinity. Try not to kill if the target isn't under the affect of Black Arrow. Have as many skeletons as you can and don't bother saving them. They are your tanks. They are disposable. Save your Crypt Fiends and the Hero only.

Once you upgraded your necropolis (should be by the time you have 8-10 Crypt Fiends), research Burrow, even before Web. Use the burrow on each Crypt Fiend that's low on health until it heals. Keep improving their carapace. Bring 2 Obsidian Statues with you: one to heal and one to give mana to your Hero. You may also have 2-4 Banshees which will further reduce the damage done to your Fiends. Although, at this point of tech-ing you usually have already killed the enemy player and can move on to next if it's a team game.

Don't try this tactic on Night Elves massing Huntresses or Orc players massing Grunts. Never target Dryads or Spell-breakers if you have other targets close. These won't 'give' you skeletons once they die and they'll keep on dispelling or stealing your skeletons. Basically, run away from these spell counters. Avoid Orc Grunts, focus on Head Hunters and workers instead. Generally pick what you can kill fast, leave the tanking enemy for later (when you have many skeletons). Killing Wisps is fun but they have no corpse, so they won’t give skeletons for you and the wood-wisps don't count much for the enemy anyway. If the enemy focuses fire on your Crypt Fiends and Hero, run away. Otherwise, kill and see your undead army rise! You might want to watch out for Wisps using detonate to kill the skeletons. - tB_Viper

Dread Lord + Abominations - Player Submitted Strategy
This strategy is useful if the enemy isn't massing air units or units such as Dryads. Create at least 6 Ghouls until you upgrade to Black Citadel. Creep with the Ghouls, avoiding the enemy if you can. Train at least 2 Crypt Fiends with Web and at least 1 Obsidian Statue to restore health. Once available, start producing Abominations. A Destroyer or two comes in especially handy against Orc shaman, Human Sorceresses and Night Elf druids. In all cases, 2-3 Meat Wagons are a must to kill enemy base efficiently. Create all of these units. Make sure your Hero is level 5 with level 3 aura. Next order your siege to attack enemy buildings one by one, starting with the towers and the main structure, while at the same time unleashing your fierce Abominations on the enemy. As long as they attack organic units and are covered with the vampiric aura as well as the healing from Statue(s), they should be ok. Whenever they go low on health, press Cannibalize. Devour all magic that's not yours. Cast Inferno in the middle of the enemy army once you can and other spells too. The Crypt Fiends are basically only for bringing down any air the enemy might have. With all abilities for your units researched and weapon + armor upgrades you can take down nearly any enemy ground army. You might have problems with mass Siege Engines. Beware of focused fire from Dryads because they can kill your Abomination very quickly. The basics of this tactic is to survive until you got at least 4 Abominations. After that, try not to lose them (that's what you need level 3 aura and Obsidian Statues for). Your army should keep the enemy busy at least as long as it takes your siege to kill the most important structures. After that, it's formality. Do not continue with this strategy if you see the enemy building lots of air units when you scout them. - tB_Viper