(Ellipses are meant to simulate his speech pattern):
Store Greeting (Pre-purchase): "Greetings..."
Purchase: "The pact is sealed..."
Store Greeting (Post-Purchase): "Make it Quick!"
Ready: "Qouvous Skorrav Torrak!"
Intro - Greeting Arthas: "I sense Ner'zul within you, human..."
Intro - Greeting Positive: "Let us teach them to fear death again..."
Intro - Greeting Negative: "You...will show the proper respect!"
Intro - Response Positive: "Very well...this should be interesting..."
Intro - Response Negative: "When my work is finished, I'm coming back for you!..."
Battle Begins: "At last..."
What 1: "Yes?..."
What 2: "I'm growing impatient..."
Pissed 1: "That doesn't hurt..."
Pissed 2: "This is the reason I ended it all..."
Pissed 3: "Stop that incessant clicking!"
Pissed 4: "I was the first, you know... For me, the wheel of death has spun many times...twice..."
Pissed 5: "I never intended to remain in the Black Temple for long...I was just crashing there for a few weeks until I could get back on my feet."
Pissed 6: "I am the first of the death knights...the pale rider of shadow moon valley... I...am Teron Gorefiend!...But you can call be Terry if you'd like."
Pissed 7: "Curse you He-Man!"
Move 1: "Whatever you wish..."
Move 2: "Immediately..."
Move 3: "Of course..."
Move 4: "Very well..."
Attack 1: "I'd be delighted!"
Attack 2: "Vengeance is mine!"
Attack 3: *Ghostly Moan*
Attack 4: "Let terror reign!"
Attack 5: "You who would stand against me...Prepare to die!"
Casting Doom Blossom: "I have something for you..."
Casting Shadow of Death: "Death...*Chuckles*...really isn't so bad..."
Killing a Hero 1: "I have a use for you..."
Killing a Hero 2: "It gets worse..."
Killing a Hero 3: "Do you now understand...the difference between us..."
Killing a Hero 4: "What?...Did you actually think that we were equal?..."
Killing Arthas: "The Scourge is now mine, Ner'zul..."
Killing Uther: "The shadow grows in the light's absence..."
Killing Illidan: "Outland has a new lord..."
Killing Murky (Egg lives): "The wheel of death...spins for y-(Murky Respawns)...Oh..."
Killing Murky (Egg is dead): "The wheel of death spins for you...finally..."
Respawn 1: "I'm alive!"
Respawn 2: "The wheel...spins again..."
Respawn 3: "I have alot of catching up to do..."
Ping - Kill hero: "This one could serve me well..."
Ping - Capture Mercs: "These Mercenaries shall serve me..."
Ping - Help Ally: "Our...ally is in peril..."
Ping - Help Me: "These fools are stronger then I believed..."
Ping - Destroy Fort: "Reduce this Fort to ash..."
Ping - Defend Fort: "This Fort is vital to my plans, defend it..."
Shadow of Death is also a neat concept, but the way it's laid out, there's a REAL narrow window of effectiveness where you can get it to do damage and summon things. I think it would work better as a DOT.
Still, the overall concept works together pretty well, even if it's not a hundred percent perfect. Thumbs up!
There might be a couple of things that are a bit too good, but the general idea is great, I like it. :)