[Mossy Toes]

Arg, crappy cell service keeps eating my posts. Anyways: I'm glad to see my tactica is prompting some thinking and activity!

An unfortunate hang-up: daemons can't join CSM units and vise-versa, so no Huron in Daemonettes or Tzheralds in Havocs*. Just like they can't join daemons from other gods--a jealous lot, they are. So: you need some Horrors (say, 11, not 10, for the extra warp charge) for those Tzheralds to camp in. And I would consider dropping Huron entirely: sure, infiltrating the Noise Marines and Daemonettes would be nice, but you could, say, use his points to get those Horrors and a Herald of Slaanesh on a Steed of Slaanesh who is outflanking the Daemonettes. And who has a Greater Etherblade for the nasty statline. Then t1 you could Invisibility the Havocs for their survivability.

I'd consider using any points remaining/possibly dropping a few cultists to get another biker or two, since currently that IoE costs about 6.5 points per model for that FNP. Spread the cost out a bit, maybe. If not more bikers, another mastery level or two on the Heralds.

*Something I should almost certainly mention in my tactica, seeing as I think I glossed over that.

 

[Mossy Toes]

Daemons have a special rule saying no daemon can join or be joined by another model unless it has the same "Daemon of [god]" qualification.

 

[Mossy Toes]

Nope. "Daemon of Slaanesh" and "Mark of Slaanesh" are distinct entities, unfortunately, and the only CSM with the former are Daemon Princes--and MCs can't be joined by other people to make a unit. The rule in the Daemons book only refers to the former.

...this really is something I'm going to have to mention in my Daemons: Allies section.

 

[Mossy Toes]

Hmm? Aren't the CSM still the Primary Detachment? They have 2 HS choices, for all that otherwise either half of the army could be the Primary detachment.