Is it possible to get the alt versions of the cat and rabbit to attack you in their big forms, or is not now possble atm. I was wondering what the mimic ring does and if there are other mimic items like the ring and sword.

currently there isn't a version of the rabbits or cats as a enemy after they have eaten something. however the tiger does.  as for the mimic items, its just the sword and the ring. those two items slightly increase item drops from enemy's that currently have drops implemented.  the ring increases the chance while the sword increases the amount dropped if it does drop.  there are only two mimic items currently.