Saved the best 'til last, haven't I? Well, No. I've saved the Hardest part 'till last. Because of the nature of the unit, All of the Daemon princes are reasonably strong. I decided it would be best to rate them against each other. To supplement this, I will rate the generic (i.e;, the unmarked daemon prince - I do know that it is illegal,) but I feel it is the best way to write daemon princes into the rest of the review. Note that, the generic Daemon Prince's God's Boon Bonus should be the same as the overall result for their respective entry in this post, with the overall value for the generic DP using the average value of those god's boon bonuses. As for the individual god entries, I will enter their:
Price: Price changes drastically based on which prince you take, so it is vital that it is noted down.Psychic Powers - These are a large part of what makes Daemon Princes so strong, so I feel it would be unreasonable to not rate this power.
Survivability: This one reviews how survivable the daemon princes are, in comparison to one another. Mostly, this one gives some small bonus to Tzeentch and Nurgle.
Leader Choice: This one is the overall for the daemon prince's best unlocking character - for example, a tzeentch daemon prince uses Fateweaver's unlock value, while one of khorne or nurgle will always use the blood thirst/guo because they're clearly better choices than their named counterpart.
The final score for the specific daemon prince has been rounded off to the nearest .1 decimal place for simplicity's sake.
Daemon Prince: General Notes.
Relatively cheap Flying Monsterous Creature
4 T5 wounds with a 3+ and a 5++
Access to wings and 3+ armour saves
Access to all manner of rewards
Access to 3 different psychic disciplines, plus the god's personal discipline.
T5 means boltguns can bring him down, and vindicators can potentially flatten him. Never throw one up against a wraithknight, ever.
I've assumed the Daemon Prince will always have a 3+ save and wings. I don't think one can really argue against this - it's just the best way to make the most of your investment. Daemon princes do not pack enough hits or wounds not to be flying, and can't come close to enough damage output to make charging across the board a worthwhile endeavour. Daemon princes do have one weakness, in that they have no access to divination. This is overlookable, but ensures one cannot run a screamer star alongside them.
Price 6/10 They're smack dab on huge points investment. If you're taking one of these guys, you might as well take three. Very dependent on the chosen daemon prince.
Survivability 7/10 I couldn't in my right mind give them a worse score than fateweaver, given that they get a 3+ save, but otherwise they're on par with fateweaver.
Damage Output 9/10 This is VERY subjective, and really depends on the chosen prince.
Rules 7/10 Again, it depends on the chosen prince, but usually its rules don't hurt it.
Gods Boon Bonus (Tzeentch) 7.5/10
Gods Boon Bonus (Khorne) 5/10
Gods Boon Bonus (Nurgle) 7/10
Gods Boon Bonus (Slaanesh) 7.4/10
Overall 7.1/10 They're a very good unit, but they're very pricey. You get what you pay for, but sometimes you don't pay for enough.
Tzeentch Daemon Prince
Can spam out S5 shooting like nobody's business
Reasonably survivable, re-rolling 50% of failed armour saves.
Most reliable psyker.
Access to two of the most hilarious and fantastic close combat weapons in the game.
Only Daemon Prince with reliable access to S8 in close combat.
No access to divination makes it hard to run mono-tzeentch, and can't really support screamerstar.
This one is a really reasonable infantry strafer, it's a little strange that it is in fact the best close combatant of the choices when given a greater reward.
Price 6/10 Very expensive. Easily 350 points.
Psychic Powers 7/10 FFoT is great.
Damage Output 8/10 Very decent, given that it is not what one looks for in a combat unit.
Survivability 8/10 Better than anyone else against small arms.
Leader Choice 8.6/10 Can I get a hell yes? Mr Fateweaver himself.
Overall 7.5/10 Very Strong choice.
Khorne Daemon Prince
He's a daemon prince.
No Psychic Powers, No Ranged damage unless he gets lucky on rewards.
Khorne got shafted.
Price 8/10 Very Cheap, But you get what you pay for.
Psychic Powers 0/10 0 access to psychic powers.
Damage Output 3/10 A close combat unit who's being compared to other close combat units that perform at the same rate (or better) than he does, and has no ranged damage output.
Survivability 8/10 So unthreatening he has to be an easy protect.
Leader Choice 6/10 Bloodthirster, great! so, now you get a fantastic unit that makes your khorne daemon prince even more redundant!
Overall 5/10 It's hard to like the Khorne Daemon prince when he doesn't approach useful.
Nurgle Daemon Prince
Access to shrouded
AP3 flamer option, or AP2 large blast. Or Haemorrhage on steroids.
Access to Instant death close combat weapon.
Completely outperforms a khorne daemon prince in close combat.
None really. It is fast enough that it doesn't suffer like other nurgle daemons might.
The Nurgle Daemon prince is unique, in that it can go toe to toe with even the toughest opponents. Being a daemon prince, it's got uncharactreistically high initiative, ensuring it almost always strikes first. It can topple any opponent, even a wraithknight, in close combat.
Price 7/10 Doesn't need psychic powers as much as a tzeentch daemon does, so you can drop off a point or two if you want.
Psychic Powers 7/10 Lots of good 4+ wounding shooting to be had.
Damage Output 6/10 More than khorne, less than tzeentch.
Survivability 8/10 Decent, especially given he can usually set himself up with a 3+ against any shooting.
Leader Choice 6.8/10 A good one that lets your daemon prince hide in reserve if you wish.
Overall 7/10 He's solid.
Slaanesh Daemon Prince
Pumps out S6 shooting
Access to a S6 rending beam (meh)
Potentially Stops your enemy overwatching as he launches into combat.
Can move very quickly, even for a daemon prince.
No defensive traits
Lash + Vector strike can be very dangerous.
Price 8/10 Read: Nurgle Daemon Prince, add a bit.
Psychic Powers 6/10 Not as good as Nurgle or Tzeentch
Damage Output 10/10 Most reliable damage output from a daemon prince
Survivability 7/10 threatening and has no bonuses for it, still a daemon prince
Leader Choice 6/10 KoS suffers from having his wings clipped.
Overall 7.4/10 Reliable.
This concludes my review of the Chaos Daemons codex. I've learned some things, and I've changed my mind about certain things several times. Our overall winner in this codex is tied, between Fateweaver and the Seekers of Slaanesh at 8.6. I suppose it's worth noting that they have a higher score than my three winners in the Space Marine Codex, who scored three-way with 8.4.