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I must admit i was a little bit disappointed with the current big daemon rules... It seems to me like a lord of chaos is out-and-out better than a daemon prince, and an exalted champion puts up a good fight for best hero over the exalted daemon. I mean, they just seem easy to kill, expensive, and frankly not capable of as much as a mortal chaos champion. Somebody please convince me otherwise, or at lesat agree with me to put my mind at ease!
Oh, BTW, i play a *mostly* khorne army, and i only take khorne or undivided generals.
With flying (and spellcasting if not Khornate) they can be good. Uniquely customisible with Daemonic powers, they just work different to Mortals, so a direct comparison isnt completely fair. Daemon units tend to be pretty expensive, but they are often worth it.
The point (or problem) is that daemon princes and exalted daemons have to pay for terror, flying, the extra wound, being daemonic (although this has admittedly a major drawback), and in case of the exalted comparison (daemon vs. champion) the better toughness.
The lack of decent armor for daemons is a bit difficult if you're facing lots of handguns/crossbows, but even a mounted chaos champion with the enchanted shield will botch some armor saves, if enough wounds have been inflicted (not to mention bolt throwers, cannons, or anything else ignoring armor saves where the extra wound of the daemon might come in handy)
Of course, they have to be used differently. I sometimes field an exalted daemon with the diabolic splendour attached to some horrors (at least in the beginning of the game) the horrors get a real ward save (so that at least some incoming magic damage can be avoided) and the exalted enjoys the protection of being in a unit ('Lookout Sir!' etc.) until I have manoeuvred them into a position where he can fly behind the enemy battle line (or charge a war machine or some other small but annoying unit) and force terror tests amongst enemies close by (and even dwarves will occasionally run), support other combats by joining in the fray. Granted, he neither gets the bonus for flank/rear charges nor negates enemy ranks, but his stats are good enough to cause some damage.
It ain't easy bein' green... :-)
hmmm... true. i guess for undivided its better, but not for khorne