Evidence in lore and game points to no. They are undead, but not super undead like Forsaken and scourge.
They have the Lichborne ability to become Undead, they still need to breathe (they can drown)
Koltira complains of “internal bleeding” in the DK quests. I feel like DK’s aren’t exactly undead, but somewhere between alive and undead, closer to alive.
PERFECT
you’ve hit the sweet spot, like this right here is where you need to stay
“super undead” is a new term I learned today. love it!
They’re only mostly undead.
They’re basically stuck in a hangover they can’t get rid off.
They…can be undead, but don’t have to be… I don’t think?
Arthas wasn’t undead… maybe he was a special circumstance.
It’s a bit odd. They don’t have to explicitly die and get raised (though player DKs did) but they do turn into undead. By the time he was the Lich King, Arthas was fully undead.
Maybe it’s like DnD Lich. You don’t have to necessarily be dead first. The ritual skips the dead part and goes straight from life to undeath.
They are undead. Forsaken are super undead and Forsaken Death Knight are ultra undead.
This is correct.
In fact the in-game description for Forsaken DKs are “like super dead yo”.
Death Knights are undead. They can just mimic many functions of the Living. They’re much higher-tier undead. They can feel pain (they know when they’re injured, but can ignore it) so they know when to back off in a fight, don’t get tired, and can suplex horses without many issues. With higher thinking comes emotions. They have fractured bits of their souls like Forsaken, so, the Light burns them like crazy for the abominations they are.
Yeah, Death Knights lorewise are super-strength tier. They were made to compete with paladins who are also in that tier.
If people roleplayed them properly, which I’m glad people are dumb and don’t read lore, there’s still the Wracking Pains issues (where they must cause suffering to a living being or they suffer withdrawal, go mad, and go on a killing rampage), and so on. I imagine the new Lich King can fix that, but a blue should be asked.
Sure but you don’t have to tell them about the horse suplexing. The last thing we need is D.H.E.T.A. protesting outside Acherus.
They are only mostly undead. There’s a big difference between mostly undead and all undead. Mostly undead is slightly alive.
They are super undead in the way that they have more dark magic sustening their body. Being a dk is being empowered. While a forsaken or scourge is basicly a minion. A dk is a commander of the undead so they have privileges.
Can a Gnome Death Knight suplex a Horse? 
I think its like a ‘slowly dying inside your own body’ kind of thing, so you can’t pin point exactly when they died and became undead, but yes, deathknights are infact undead.
That’s a trick question. Everyone knows they’re not real. The Lich King just made them up to scare young DKs into eating their plague and brains soup.