A. For Leviathan: in the WOR go to South Figaro to learn about leviathan, then take the ferry in either South Figaro or Nikeah and you'll get into an underwater fight with leviathan.

For Giant Cactaur: In the WOR talk to the man to the left of the entrance to Maranda to learn about the Giant Cactaur, then go to the desert south of Maranda and kill 10 Normal Cactaur, then go to the Southwest corner of the desert and you'll get into a battle with the Giant Cactaur.


Q. What is the level up bonus you receive if you have the Leviathan and the Diablos Magicite eqipped?