Using only actual rules as written I am curious how people feel about the following idea: A Herald of Slaanesh joining a unit of possessed csm with the mark of Slaanesh.
In the Daemon Codex the following restrictions are listed (p26)
Daemonic Alignment: Daemons can only join units that are comprised entirely of Daemons with the same alignment as themselves (i.e. a Hearlad of Slaanesh can not join a unit of Plaguebearers).
Daemonic Instability: A unit with this rule cannot be joined by a model without this special rule.
Note, no restriction disallowing a model with this rule from joining units without it. Am I reading more into it than is there, or is it possible. Keep in mind it would only work daemons, so possessed from CSM, but it would also affect units from the new Khorne book.