Note - I will discuss special characters in a future post ;) .
Keeper of Secrets
The KoS is perhaps the fastest striking unit in all of 40k as it has a impressive initiative 10. The other stats are typical monstrous creature; WS8 BS4 S6 T6 W4 A6 LD10 4+ inv. All this costs 200 points including the daemon gifts mentioned below.
Daemonic gifts; the KoS gets aura of acquiescence which are frags and defensive grenades. Special rule wise it of course has the daemon rule (so do not forget those fear tests each round of combat) and also fleet. Fleet is handy as it allows re-roll assault distances (one or both dice) or re-roll running distances.
Transfixing gaze allows you to reduce the attack of a enemy model in base contact during close combat. This is very handy for making a power fist model have limited attacks. This gift only costs 10 points, so if you have the points then splash out.
Soporific musk gives the KoS hit and run. With I10 the KoS is going to need a 6+ to fail the test. Extremely handy if your opponent has bogged the KoS down in combat or you want to escape combat to recharge.
Pavane of Slaanesh is the mini lash move about trick. You'll notice that all the cool stuff for greater daemons is pretty expensive. For 25 points I am not sure if I would bother. Don't get me wrong I am a huge pavane fan (I run the Masque) but one shot which has 66% chance of hitting, well is it really worth the point cost?
Daemonic gaze is a S5 AP3 assault 3 shooting attack, for 15 points it's not too bad. If you have spare points then grab it.
Unholy might gives +1 strength. As monstrous creatures have the smash rule, then you can be S10 and with the KoS being S6 base, you're wounding most stuff on a 2+. I would probably leave this one at home.
Instrument of chaos is only 5 points, might be handy if the KoS doesn't do enough damage. Basically it lets the daemon win combat if combat is a draw.
The best setup for a Keeper of Secrets is transfixing gaze and soporific musk. This makes the KoS 230 points in total, any more points and you're struggling to justify the points cost. I wouldn't add anything else as the gifts are too expensive or do not suit the Keeper's close combat role. I would add the instrument if I had 5 points spare though.
As the Keeper is a close combat unit, then you're best sending the Keeper on HQ or character assassination roles. Use the I10 to strike against characters first and the gaze to reduce their attacks. If combat remains, then use the musk (hit and run) to run off and re-charge in your combat phase.
I've been told this fella called Mephiston is a bit of a bad ass. I'll use it for a go compare. Yes I know he has no invulnerable save, but this is the pit fall of the (not so) mighty Mephiston.
Keeper charges Mephiston and gets 7 attacks. Keeper strikes first and hits with 5 attacks and wounds with them all; good bye Mephiston.
So, that's how handy the Keeper is in combat. Just remember, don't send the Keeper into a unit of Hammernators or else he will get his face beat in.
Great Unclean One
The GUO is the cheapest greater daemon costing a bargain 160 points. For that cost you get WS6 BS4 S6 T6 W5 I2 A4 LD10 4+ inv.
Standard gifts/rules are noxious touch (poison wounds on a 2+), slow and purposeful, feel no pain and daemon.
Cloud of flies gives assault and defensive grenades. For 5 points this upgrade is a bargain, though the assault grenades won't come in much use. Don't forget the stealth rule if a unit is within 8" firing at the GUO, this maybe important in the right situations i.e cover.
Aura of decay is a waste of points. It inflicts a S2 hit, on a Grot it would need 4+ to wound. Leave this at home.
Breath of chaos is very handy, glance tanks to death and incinerate infantry. Very handy when going into assault.
Unholy might isn't required. As mentioned about the KoS, all monstrous creatures have the smash attacks and the GUO wounds on a 2+ anyway.
Instrument of chaos is exactly the same as the KoS.
As the GUO is cheap, you can afford to splash out on the daemonic gifts, though is it ironic that most aren't useful? I would definitely take the breath of chaos and because cloud of flies is only 5 points I would take that; defensive grenades may come in handy and you never know stealth might too.
The Great Unclean One is best used as a tarpit monster. Send it to tackle elite close combat units such as Hammernators or intercept fast moving assault units such as Wraiths. The 4+ inv save as well as feel no pain should mean the GUO will keep those units locked in combat, as well as the GUO laying the smack down with with AP2 attacks which wound on a 2+ with re-rolls. In time the GUO may need some reinforcement, so don't go thinking the GUO is the daddy in c.c, he's just a tarpit unit and also a cheaper greater daemon.
The BT is the joint most expensive greater daemon. It costs 260 points and you get WS10 BS4 S7 T6 W4 I5 A5 LD10 4+ inv.
Gifts/special rules are; daemonic flight (wings), iron hide (3+ armour save), daemon and furious charge.
Death strike - basically a 12" plasma shot for 20 points; leave this at home.
Blessing of the blood god gives a 2+ save against wounds caused by force weapons or psychic powers. For 5 points this is bargain, especially if your meta area is heavy with Grey Knights and/or psykers.
Unholy might gives +1 strength, for 20 points it is expensive but worth it on a BT. Firstly the BT will be a whooping S9 on the charge thanks to furious charge. Then the BT has wings, so can do vector strikes which makes those attacks become S8; evil, especially if on side armour of a vehicle.
Instrument of chaos; you know what it does ;).
The BT has limited but useful daemonic gifts. I would take the blessing and unholy might gifts; a S9 M.C on the charge is wicked and a 2+ save against psychic powers and force weapons is just too good not to have.
Like the KoS, you could use the BT for character hunting, but being I5, some characters may strike first or at the same time, though it's not like those characters are going to do a fat lot! Instead I would use the BT for dedicated vehicle hunting, S9 will easily mash up vehicles, but if against av14 of course use smash attacks (remember you can re-roll armour penetration). If the vehicle has a unit inside, well they are going to get mashed up by the BT need turn, unless your opponent can drop a huge amount of fire power.
Lord of Change
Like the Bloodthirster, the giant chicken also costs 250 points. You get WS5 BS5 S6 T6 W4 I5 A3 LD10 3+ inv.
Gifts/special rules are; soul devourer (enemy model takes a leadership for each wound suffered, if fails instagib), daemonic gaze, bolt of tzeentch, daemonic flight and of course is a daemon.
We are legion allows the LoC to split fire; very handy considering the LoC can fire multiple weaponry.
Master of sorcery allows the LoC to fire another weapon, as it is a monstrous creature then it can fire two shooting attacks and now fire a third all for 10 points.
Breath of chaos is extremely cool, what's not to like?
Boon of mutation can force a enemy model to take a toughness test, if the model fails then it is turned into a chaos spawn. This power is very situational, and while it can be fun, I am not sure if 30 points is worth it.
Instrument of chaos, do I really have to say about this again? ;)
The Lord of Change is your shooty death laser chicken and does shooting nicely. But, the points cost is a issue.
You could multiple Heralds for cheaper and while they do not shoot as well, they only need a 3+ to hit.
Daemon Princes can also take a bolt and with wings, iron hide and mark of tzeentch they would cost about the same as a LoC and be handier in close combat.
Really I would just take Fateweaver, who costs 333 points. While Fatey is slightly weaker, he knows all tzeentch powers and then some. Also gives re-roll to saves to any friendly model within 6". If you add the gifts I would take to a LoC (we are legion, master of sorcery & breath of chaos) you're talking 330 points right there.
When you have the option to take Fateweaver, there's just no need to take a Lord of Change. If you want more shooty in your HQ, then take two Heralds of Tzeentch with bolt; two bolts are better than one.
That's it for part 1 for the Chaos Daemon HQ tactica. Part 2 will be all about the Heralds. If you have anything to add or just want to tell me your thoughts and experience, then get commenting in Disqus :)