Again, the
recent 'Ard Boyz legal armies list covers how Inquisition handles new allies' codices, and what is and isn't allowed to be allied in the 'Ard Boyz tournaments. As these are
GW-sponsored and sanctioned events, with
GW-written scenarios and rules, this is the closest there is to an authoritative answer until the Witch Hunters and Demon Hunters get new codices, or
GW updates the existing
FAQs.
Allowed troops allied choices: Space Marine Tactical Squads, Space Marine Scout Squads, Imperial Guard Infantry Platoons, Imperial Guard Veteran Squads (Upgrade characters cannot be taken)
Allowed fast attack allied choices: Space Marine Assault Squad, Land Speeder Squadron, Space Marine Bike Squad, Scout Sentinel Squadron, Armored Sentinel Squadron, Rough Rider Squad, Space Marine Scout Bike Squad
Allowed heavy support allied choices: Space Marine Devastator Squad, Space Marine Land Raider (including Crusader and Redeemer variants), Space Marine Dreadnaught, Space Marine Predator, Leman Russ Squadron (Pask cannot be taken)
The 'Ard Boyz rules leave the Elite and
HQ entries in the normal Inquisition codices un-modified.
All of the above are outlined in the C:
SM and
IG codices. s2ua7: There are two "command squads" in the
IG codex. There is a "company command squad," which is an
HQ, and there is a "platoon command squad," which is a required *part* of a platoon.
FRFSRF is an order available to the platoon command squad.