Fist of all, you should have 99 str or atk or they both should add up to 130, then enter the warrior's guild and do some activities, you will get some points, go to the top floor and talk to a lady there, she'll tell you some stuff, then enter and start killing the Cyclops, you will start out with a Bronze defender, now go and give it to her, now you have increased your chances of getting a dragon one, repeat till you get a dragon defender! Hope it helped you! :D