So im just curious about something.
lets say I want to make a faction of monsters but I dont want to use the Beists classes, could I take hybrid beist in my faction with the bonus enviroment adaptation trait Monstrous beast 20pt? it would be slightly more expensive depending on traits but i dont see anything that says its strictly restricted to the Beist faction.
Yes you can do that. There are a couple different ways to do it.