Well, um... Two days, unless Frostwhisper extends the deadline. :/
Moreover, my mid-term paper is due next week, so this weekend will be clogged. I mean, it's not so bad if we can work out "simple" alternatives... I'm just not making any promises.
Dangit dangit dangit... I didn't think I'd actually convince you.
~~~
But let's just assume.
We've got the Undead hero almost fully made, same for the Undead unit. All they need is the building (which, feasibly, could just be a bigger version of the Plague Cauldron you modelled on the bear)
(wait, upgrades??)
Since we never actually decided on the other race, I could never begin work. But I submit that Humans would be super-quick.
Hero
(Hero ideas from the old Discussion thread, since I don't care anymore about secrecy

)
Humans: Crusader, Avatar of Light (see Seraph)
Dwarves: Marksman (rifleman hero), Shaman/Berserker (from the feral "Wildhammer" clan that rides the Gryphons)
Blood Elves: Waywatcher (ranger hero), Blood Knight
Unit
(Unit ideas also from old thread)
- some sort of War2-esque Paladin upgrade for the existing Human Knights called the "Crusader".
Would become like a caster (3 spells), but retain all it's Knightly power. Would have a Reveal-Terrain ability like the Far Seer's; only this would give Line of Sight in an actual Line, from the Crusader to the target point! (actually, this spell could/should be used on any custom unit...). That and Exorcism, probably; something that deals mega-damage to Undeads only. Damage + slow.
some sort of "Outrider" unit that would act as fast-moving Scout and speciality unit.
See, you could use it to Scout, but it would also have an "Outpost" ability that would allow for faster expansion! (like, a "ward" that would increase the build-speed of nearby builders, or a "ward" that, when clicked on, became a half-built Town Hall)
Either of these could work. For the "Paladin Knight", just mess with the Garithos/Knight model; mix some stuff up and give him some glowy eye particles.
For the Outrider... Meh, a Peasant with a rifle on a horse?
Building
I have no idea. But if we're going with the holy theme (holy hero, holy unit, etc), we could make some kind of "sun-focusing" tower, which would be empowered with the holy light to CHARGIN ITS LAZAH at enemy units. Possibly a boost in damage from other nearby "sun towers"?