Each Natural Island and Fire Island has one Single-Element Mythical Monster that can be bred on it. Each one has its own unique combination of Monsters you must breed in order to obtain it. Discover the breeding combinations by breeding different Monsters!
Even if you’ve figured out the correct breeding combination, you may not get it right away. Try lighting your Wishing Torches to increase your chances of success!
Once a Mythical Monster reaches Level 15 it can be teleported to Mythical Island, where you can start breeding them to discover more Mythical Monsters.