Add 10 bats, 5 dimorphodons, 2 centipedes, 3 spiders, 1 rex,1 giga, 2 purlovia, 2 bears,1 theri, 2 griffins, 1 bronto. Get them all to high level with points in damage health mainly, speed for the bats and dimorphodons and I am pretty darn sure no one would get near your base any time soon.