Well quite frankly, this game is tedious and frustrating. The "fever" combo bonus thing appears to do absolutely nothing but give you a different background, the "debris" seems to have a hitbox the size of the entire screen, while baloons have a tack sized box. Interesting game. Still enjoyable though.
I find that it takes an extremely long time to find even 10 of the bestiary inquirments. Throughout an hour of time on every mode on every difficulty I haven't found any more.