It's on the wiki Kay, but also here
http://forum.shinobilegends.com/index.php/topic,7768.0.htmlIt's only one rule that concerns biju. But it's not just the users who made it, it was a lot of people and a huge thread that can still be found. Anyone may comment on them or this thread by extension.
Well, I agree and disagree with you Camel. I think they should be able to, though not without regulation.
If allowed, my guidelines would be
Only Unbound Zombies may host. Bound zombies may not. Since Unbound Zombies can't use ET this avoids someone pulling a Obito. Meaning someone like Bocc couldn't have put his biju in his zombies.
Unbound zombies may never use a full transformation. Considering it's a biju rule where you must be transformed to do a biju bomb, this means an edo host can never use a biju bomb.
Basically just give an unbound zombie the right to use their biju's abilities (in my case Yoton) and use the biju cloak.
Heck, take away the v2 cloak, and do the opposite tax of a summon. Biju that are sealed within a zombie, lose 20% of their chakra. While the Edo is infinite, biju are not.
But if people like yourself overwhelmingly hate the idea, than that's all there is to it.