More Monstrous Companion’s?

[Naga-Darmag]

I have found the Beast Heart Adept prestige class (http://www.wizards.com/default.asp?x...070209a&page=4) and I like. I’m considering making one sometime, the only thing I don’t like is that the list of possible Monstrous Companion’s is so short. Especially for something that has come so shortly before a total system change (in other words not to likely to get a expended list in a later bock). If you play in a specific environment and/or chose to specialise in ether magical beasts or aberrations the list quickly runs dry. My question to you is if there’s a expended list somewhere using more then the first monster manual or if there’s some rules for adding new creatures to the list.

[Bag_of_Holding]

There are no 'official' expansion of the list, but you can quite safely expand the list within the normal limits (similar CR, size, type etc). You'll have to ask your DM first though.