Instructions
Capture at least one male monster and one female monster if you do not have any already.
Use the two monsters you intend to breed in battle until they have each reached at least level 10.
Return to GreatLog and enter the Starry Shrine.
Speak to Professor Monster, then choose "Breed."
Select the "base" monster to be bred. This determines the new monster's family.
Select the "mate" monster. This determines the new creature's monster type. The two monsters then produce an egg but leave your party permanently.
Speak to Professor Monster again and select "Hatch Eggs." Select the egg that the monsters produced. Professor Monster charges you an amount of gold equal to 10 times the new monster's starting level.