You need beasts with strong genes.
Attack genes - especially blind/roar/shriek/music/petrify and elemental attacks
Defensive genes like robust scales
Regeneration
Thick skin increases hit points
My advice, to get a good base stock, go into breeding offers and look for great sires that have offspring in the pound, and adopt those. Much cheaper than buying the finished product and you get to breed to where you want to go yourself, which is fun.
Whoever calls on the name of the Lord shall be saved.
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