As a player of Warcraft III expansion pack and the undead race, there are a
few corrections needed to be made the death knight's abilities:
Death coil: Still does the heal/damage mentioned above. To pick a
great chunk out of an enemy hero, a lich is usually used, so that a coil
closely followed by a frost nova hits the enemy hero. This is generally
called a nuke. Death knight is chosen first for his coil because undead do NOT
have a tier 1 healing move.
Death pact: buffed considerably, but still not picked much by
players. It now returns 100/200/300% of the sacrificed health.
Unholy aura: chosen as the second skill of the death knight,
sometimes even as the first to get a few nice early surrounds on night elf
heroes. Gives 0.5/1/1.5 hp regen/sec, and gives 10/20/30% bonus movement speed.
Ghouls with frenzy and this aura will make them quite alarming even at tier 3.
Resurrect: Yeah. Crazy ultimate of Death knight. BUT. As coil/aura
are quite imbalanced when both at level 3, so some opt for resurrect at level
7. The 6 corpses raised are now invulnerable to all attacks/magic, and last 40
seconds.