REALLY EASY EXP
First you need to have beaten the Pride Lands world.If you have beaten it,go there again,equip the gullwing keyblade which you get from the three fairies in Radiant Garden.From the customize menu,make donald,goofy and Simba not to fight but support Sora while he is fighting.It's called "Sora Attack".Then take all the potions and healing items from them and unequip all their abilities.Equip Sora's experience boost ability which gives more exp for each enemy Sora kills with HP lower than 20%(when his life's flashing).Then go to the area over Simba's Throne.It'll be full of these small yellow monsters.Don't kil them as soon as you get there.Just stand back and let them hit you until your life is flashing.Then kill them all without using magic except magnega,it's really helpful.If your life is flashing,each monster will give you almost 200 exp instead of 65.
WARNING:It is vital that you make your party not to fight because the monsters they kill give you the normal amount of exp.Also,it's vital that you take their potions and healing abilities,because,as your life is below 20%,they will heal you,and you'll need to get your life flashing again.
Hope I helped!
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