It's been almost 5 years since the "Favoured of..." mechanic dropped, and old Gee Wiz managed to make an extra one (Hashut) before giving coaches any reason beyond flavour to pick Undivided, Tzeentch and Slaanesh. In the next edition it might be that some stars turn out to be Undivided to give that a reason to be (excluding them from Khorne and Nurgle and so on) but unless teams for Slaanesh and Tzeentch are released, there probably won't be any god-specific stars either.
Death Zone does not have anything for them either (or for Khorne, for that matter). I forget if the Chaos League or Chaos Cup rules that were released on Spike at some point had something for them...
Here's a wishlist, of sorts, of what I'd like, and maybe I theorise, the two missing teams to end up like.
First let's look at the two existing ones. Both have their own specific lineman, in place of the Chosen Beastman Runner, which becomes a 0-4 positional with an extra skill in tune with the other positionals. The Chosen Blockers receive a Mark and therefore become more specific in both statline and skills. The Big Guy on both counts has the same skill(s) the blockers have, and have something else, unique as a starting skill/combo, on top of that. There's the blueprint!
What Khorne lacks is something similar to the "first kill" mechanic that Nurgle has. I'd like to see that fixed, because it bugs me that beyond star access the rule currently does nothing.
Favoured of Khorne teams should instantly receive a free Reroll for the first "Death" casualty the opponent suffers, to be used before the end of the drive. Similarly,
Favoured of Chaos Undivided teams should receive a temporary (till the end of the game?) chosen Mutation on a randomly determined player on the first kill the team causes.
Favoured of Slaanesh and
Favoured of Tzeentch teams I'm not sure about; the first TD scored seems more fitting because of their more subtle nature, so I'd say things like a free reroll, or a free temporary mutation as detailed above for Undivided.
Regarding the teams, I see Slaanesh as an annoying, obstructive team. They should be a tad faster than other chaos teams, and somewhat less armoured. Their linemen, the Cultists, could be run-of-the-mill hobgoblin-like chaps with a Mutation, such as Extra Arms, ideal on and off the pitch due to their cultish rituals. Their goats, the Slaangor, should start with Claws, like the
current AoS models and countless
classic metal
figures. Their blockers, the Thrillseekers, should exchange one point of Armour for one point of Movement, and gain the super-annoying Prehensile Tail. The big guy, which should continue the "SomethingSpawn" pattern from the two released teams (but I've not come up with a decent idea for the name), should also have Prehensile Tail, and Hypnotic Gaze on top of that. Imagine a eldritch horror with a siren scream, a slythering and whirling mass of limbs, piercings, mouths... something out of the Liber Chaotica, with a statline similar to a Rat Ogre, 6/5/4+/-/9+ territory. Animal Savagery would fit the masochistic streak you'd expect from Slaanesh.
Tzeentch is a different beast. I have in mind the lumbering empty suits of space marine armour of 40K, but also the screamers, the flamers, the disc-riding sorcerers of WHFB, and also the Silver Tower range that was turned into a
convincing unofficial team with somewhat wacky rules. That team used all the miniatures the Silver Tower box had, and therefore sported a Sorcerer, a Big Guy, Tzaangor and Acolytes, and also little daemons that could split in two mid game. Back when the ruleset was young, a lot of these "mockup teams" circulated the community.
The blockers, tentatively called Lightbringers or Truthseekers, I'd like to be a callback to the Thousand Sons Rubric Marines. Make them slower and sturdier, so MA4 and AV11+. Give them Breathe Fire, now that it's a thing, and because with their third eye shenanigans they can see in the past, the future and the subjunctive, they should have Pro on top of that. The Big Guy, a flightless bird-like Firespawn, should have both of those and the Bombardier skill on top, with a Troll-like statline (4/5/5+/5+/11+) and could be either Bonehead or Really Stupid. This way, both teams have a sneaky cagebusting trick that other chaos teams lack, but less reliable than other teams who have the same mechanics. For their goats, the Tzaangor, Leap plus VLL fits what the new AoS models look like, with their legs ready to spring and the flightless bird theme. Finally the
Acolytes, their linemen, could have the same statline as Khorne and Slaanesh linemen, with Big Hand as a callback to the Blue and Pink Horror
classic models, in place of the Frenzy and the proposed Extra Arms.
Regarding prices, I reckon 50k for the linemen, 70k for the goats, 110k for the Chosen and 150k for the Big Guys. Rerolls at 60k, for poor Nurgle too. Skill access pretty similar to what already exists, but we could swap in A for S in the Slaanesh team between Primary and Secondary. That should be all. I know other versions exist, but it's fun to speculate. Let me know what you think.