Attack Type: Normal
Armor Type: Hero
CANNOT ATTACK AIR
Hotkey: D
Favorite Quote (Evil Arthas): "Who is this 'Darkness' anyway?"
Abilities:
 Death Coil: This ability is for healing Undead units, or damaging the living.
Cannot be cast on enemies it will not hurt, allies it will not heal, any form of mechanical unit,
or the Death Knight himself. Practical uses of Death Coil: Group select your army,
tab to your Death Knight (if not there already), and heal any unit you see go into
the yellow, orange, or red. Also use this on enemy living heroes (any other unit is a waste,
better to heal your own). Can attack air units, as far as I know, so if there's a living
flying unit annoying your Abominations, Death Coil it. Another good use, should you
choose to only heal one type of unit (Necromancers perhaps?) you can have a hotkey group
of only your Death Knight and the units you wish to heal. Perhaps, if your ally is
sharing units and is also Undead, you can hotkey your Death Knight and any heroes
wishing to benefit from Death Coil.
75 mana / Cool down speed : fast
Level 1 : heals 150 hp for friendly undead units / damages for 75
Level 2 : heals 250 hp for friendly undead units / damages for 125
Level 3 : heals 350 hp for friendly undead units / damages for 175
Hotkey: C
 Death Pact: This is a great spell for the Death Knight.
It's pretty much the self-healing spell that the Human Paladin lacks.
If you can, it is best to use this on units that are going to die anyway
(such as summoned units, such as Skeletons). Practical uses of Death Pact:
Press F1, control-shift click a Skeleton (should be more than enough) and Death Pact away.
75 mana / cool down speed : moderate
Level 1: 50% conversion
Level 2: 100% conversion
Level 3: 150% conversion
Hotkey: D?
 Unholy Aura: I'm a big fan of auras, especially in team games.
If you can keep your hero alive (and for all the time up until he dies if you can't),
EVERY unit on the battlefield will benefit from this (your team only of course).
Unholy Aura can benefit every single unit, flying or not. I also think a Death Knight
looks silly running around without at least one point in this. The enemy can tell
you have this skill even with a glance, so he'll know a level 1 Death Knight will not
have either of the other two skills. In return, he'll know if you /don't/ have this as well.
Practical uses of Unholy Aura: Team games, plain and simple. This will increase your
regeneration (without this, Undead will not regenerate off of Blight) as well as movement speed.
Passive Aura
Level 1: +10% movement speed; +50% life regeneration.
Level 2: +20% movement speed; +100% life regeneration.
Level 3: +30% movement speed; +150% life regeneration
Hotkey: V
 Animate Dead (Ultimate): This is a great skill (most Ultimate ones are).
Use this when there are at least six corpses and especially when you're not using
too many Necromancers (they'll steal your corpses, usually). This will revive any
corpse, so you can just kill six of the enemy and resurrect them. However, you will
get this unit back only partially with a timer and no skills, so essentially 'borrowing' them,
after they died. The spell will automatically select the 'strongest' of the corpses
should there be more than six. Your units, your ally's units, enemy units, all are
now yours to command for the duration of the spell. Practical uses of Animate Dead:
Against any player except Undead (and against them too, if the corpses aren't disappearing too quickly)
just group select your army, and when six or more die, cast it. You can tell when
six or more die easily (if you have a large army) by selecting a group at random,
so you have 12 units, and waiting until the group is down to one row again.
You can also cast this after any battle, period, even if you won, because if it was a big
enough battle, there will be some corpses to animate, and that way you are not
wasting the spell by inactivity (you can cast it again fairly soon, or you can not
battle again until it's ready). Like all Ultimate spells, this spell by itself can
turn the tide of battles, and even the war. Be sure to keep Animated units active,
as they are on a timer and will be wasted if they stand around. Since this will
pick the strongest six corpses (and Necromancers will pick any corpse) you may wish
to cast this before activating Autocast on your Necromancers, since Skeletons are
equal no matter which corpses are used, whereas Animate Dead is not.
300mana / cool down speed : extremely long
Hotkey:A
Practical uses of the Death Knight:Healing, regenerating, increasing movement speed and regeneration in nearby units,
and animating slain enemies. There really isn't any 'tricks' with the Death Knight,
just use his skills well. Like any unit, he can be put on invisible and you can scout with him.
An invisible unit, as far as I know, will NOT provide aura benefits to others (this would allow you to know where that unit is,
I guess is the reasoning) but the moment he's visible again it will.
Auras are useful in team games if you're semi-good with the Death Knight (DK for short).
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Carrion Swarm: A little used Dread Lord spell (except when there's multiple Dread Lords on the same team)
this is supposedly a very damaging spell by itself. I guess if you've got nothin'
else to do (I usually either win or lose before I get past level 7, since I use two Undead heroes;
this and the DK) you can put a point in here and test it out. Practical uses of
Carrion Swarm: From the description, it says it can deal quite a lot of damage
(but a certain amount per unit) if used correctly. This spell may be underestimated.
Perhaps putting only one point in Sleep (since the initial stun is the main
point of it, not the duration) and pouring points in here can be useful.
Sleep: Useful spell, a good Stunner. While not actually 'stunning' the unit
(they can wake up) it performs the same purpose. The only tactical advantage
of putting more points in sleep is longer duration for lesser mana. Practical
uses of Sleep: A good Stunner, and to stop enemy heroes. If the other player
attacks the unit to wake it up (which is an option) that will be one less unit
attacking you, and one extra unit attacking the hero (even if it's only for a moment
), which can be useful. It also requires that extra bit of micromanagement on
the enemy's end (to attack the hero and to also stop attacking it).
Sleep can be Dispelled. You can cast Sleep on a sleeping creep (try saying that fast),
which, ironically, will wake all the other ones up. This is a good way to start a creep battle, early on.
Vampiric Aura: Allows the Dread Lord and all other friendly melee units in the
area to 'suck' life with each attack. A semi-form of healing, that when combined
with the Unholy Aura, is very useful, to Ghouls and allied melee units
(the Undead Auras combined with Orc's strong melee and melee support (and even
the Orc's auras) with the ranged benefits of the Undead (and their spells)
can be very powerful, leading me to believe that Orc-Undead teams are one of
the strongest, offensively.) Practical uses of Vampiric Aura: Works well with Ghouls. It may be wiser to get this as your second hero if your ally is Night Elf, so that the more proper Aura is in higher levels.
Passive Aura
Inferno (Ultimate): A huge bonus (because by that time you're gonna win/lose anyway)
this is a handy little spell that deals damage, summons a very good unit,
and can stun a target (as well as clear trees). But like I said, you're usually
going to win/lose by this time (especially if you've got a Death Knight with you).
It's just a cool little spell to rub their faces in it. Practical uses of Inferno:
The actual 'Stunner' (since Sleep doesn't stun) that will also stun more than one unit, as
well as being very powerful in itself. Can be Dispelled (deals damage,doesn't instantly remove).
See Infernal.
Frost Nova: Dish out major damage. Trust me on this one. It also slows whatever it hits.
More powerful than most people credit it for. Good Hero killer.
Practical uses of Frost Nova: Killing and slowing. Good way to slow the enemy so you can flee, if you want to.
Best used when there is a whole lot of enemy units near the target.
Frost Armor: A good defensive spell, this will reduce damage and slow any melee that hits it.
Not quite as useful against Night Elves (and their lack of melee) but it will still provide armor.
Great for casting on things that already have lots of hit points (such as Abominations and heroes).
Practical uses of Frost Armor: Casting on the Lich itself as well as allied heroes.
Dark Ritual: Basically the same thing as Death Pact except for mana, this will kill a unit and
convert it to mana for you. Useful for the spellcasting Lich.
Practical uses of Dark Ritual: Similar to Death Pact, just select a whole lot of Skeletons and
kill them off for your Dark Ritual, allowing you to cast all your other spells like crazy.
Death and Decay (Ultimate): The ultimate building/unit destroyer. Since this damages on a percentage basis
(in fact the only skill I think that does, the only other percentage basis-type skills will heal you) this will kill
ANYTHING in 25 seconds (a little longer if they're healing/repairing in the meantime). Including Town Halls, buildings, or anything.
It lasts for 35 seconds, as well, for overkill (or if units wander in and out). Can be used on trees if you want. Practical uses of Death and Decay:
Cast this on enemy buildings and watch them go bye-bye. Especially Human buildings, especially towers and Town Halls.
This skill can be Stunned so make sure you kill the Stunners before activating this spell. While Blizzard is toned down from Warcraft II,
Death and Decay (equal then) has been if anything increased. Use this.