Well yes, Liches are Scourge Mages. Just like Blademasters are Orc Warriors, Beastmasters are Orc (faction) Hunters, and Demon Hunters are Night Elf Warlocks.
Of course the WCIII heroes don't match exactly to WoW classes, but there you have it. Blizzard broadly grouped up the classes (which were different from race to race in the RTS) into WoW classes which are uniform for each race. If they want to make a DH class then they need to effectively undo that, which either means removing the core aspect of the Demo tree for Warlocks or making the WoW Demon Hunter very different to the WC3 version. Either of those will make a lot of people unhappy of course.
P.S. The DK frost tree is pretty much brand new, there's nothing like it in the WC3 or WC2 Death Knight abilities.
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Only thing they took from Dreadlords was Carrion Swarm really. And Liches? Well, DKs kind of got the "flavour" of frost I suppose, other than that not really.
I'm very tempted to create a "Rejoice! Tinkerer is already playable in-game, but not clear enough, apparently." thread, then list all the Engineering profession tinkers, mounts and gadgets. LOL. :3
We don't need Demon Hunters in this game, and we warlocks are not demon hunters. Thanks
And sleep, this is why demonology warlocks are disguised Dreadlords!!!Yeah, Demonology Warlocks got Carrion Swarm...
Need to fix something.Which is why you're never getting a Dreadlord race