Yeah this'd be a very quick way of suddenly finding yourself uninvited from my apocalypse games. Apocalypse is about the spectacle, not rules lawyering. If the person/people on the forces of order side are already being this difficult about army selection and trying to impose their will on what their opponent can/can't play with then they'll probably be an absolute nightmare once the game starts. Expect hours of nitpicking arguing how the apocalypse rules interact with 7th.i know i trying to include everyone in a themed game but the marine players as like we want full as wriitten rules with no changes and you guys to play chaos which in my eye is they wana play a complete 1 sided game coz 1 on the marine players has 5 knights and no1 on the other has any superheavys
Actually unless i'm missing something and they've changed the rules (I play 6th ed apocalypse) page 18 of the apocalypse rulebook pretty much blows their argument out of the water.
pg 18 Apocalypse rulebook "Armies may include any number of units from any codex, plus any number of fortifications and apocalypse formations. No force org restrictions apply to the army. In addition ignore unit restrictions that are normally limited 0-1 or that say you must field one of x to take one of y.."
pg 19 Apocalypse rulebook "Remember you can bring along units from more than one codex."
Heck there's nothing to stop your CSM player from fielding say a helldrake and then running the marines using loyalist rules.