Ok quick question to everyone who might know the answer to this, what are the rules on combined armies.
my eventual plan for the Army of Lexx is to have my main army comprised of a few companies of Imperial guardsmen supported by Imperial armour then have a few Space maries recruited into service and fight along side the imperials with a few Space marine armour units supporting them.

this isn't to be mistaken as a allied army helping out this is to one whol army under one banner fighting together.

so if anyone can advise and let me know if this a feasible idea or not pleale tell me.