What does Ratio mean when you are in the bestiary looking up monsters? Some say like 0.9 or 1.3...

I think it's relating to combat lvl and hp. If experiments were listed, it would be 4.0. Since it's 25 combat and 100 hp.

So for training you'd want ones with a higher ratio, because you get more exp. per kill.

The ratio is their hitpoints divided by their combat level.