hi!
put cats in this way: ghost cat, wood, scottish fold and caticorn. level up the back cats, the front cats are just there for damaging and also for taking the hits instead of necessary cats.
level all cats up to over 40 damage. caticorn especially. wood would be easy to get to 40 damage as he has a max of 75 damage (also cerbercat's max).
have caticorn over 200 health, caticorn is the most necessary cat in the team. wood does good damage but has a very low health, they and cerbercat have the 2nd fewest health (max health of 320, the fewest health are comfort cats excluding fire cat [pixel cat] with 310 max)
target the other cats first than ice cat. ice cat has magic, and may heal the team members fast. however, it's better to confront ice cat with caticorn at the end (make sure caticorn has a damage OVER ice cat's, ice cat has 43 damage at the time of first battling them)
swim damages water, feed and deal damage ice cat.
wish you luck!