I would vote the Zombie Dragon gets listed as a "Undead" creature type for the purposes of game mechanics, if it isn't already. Anyone check the combat log for damage info when fighting the Zombie Dragon with anti-undead abilities (Holy, crusader, turn undead)?
The Zombie Dragon doesn't carry the "undead" attribute right now, so it isn't affected by clerical powers. But I agree, it would make sense for any creature whose name starts with "Zombie" to be considered an undead.
I didn't think the Z. Dragon was currently "undead" (I'd remember that, right?), but it's good to have confirmation. Having it "undead" would make a lot of sense and be a nice little treat for all those anti-undead cleric builds who hate fighting red dragons.
So, how many bottles of friguld rum do we need to buy David to make this happen?