Go to the first level in multi player (play alone) and go to the part where you make the boulder bust down the wall. Now when you enter the next room just go straight and you should see a big door. Go in and you should see a crystal. Go all the way to the right of the room and you should see a ledge with an indentation. Drop a magicite NEXT to the small pit in the ground. Jump on to the magicite on the ground and jump on to the ledge. Go in to the door on the ledge (push a block on to the button to open it). Go up the ramp and use a fire magicite on the red alter thing. Now go in to the door that the alter opend. You should see lots of candels. Don't bother lighting them. Go to the back of the room and lay down a magicite. Get on the magicite and hop up to the ledge and travile to the other ledge and you shouold see a chest open it and there will be an ice pocket a thunder pocket and a fire pocket. Grab them and exit the stage. Repeat.
Remember the moogle near the save crystals that give you stamps when you find them,well try to lift them up... You will be carried(fly) by the moogle while the moogle drops items (mostly magicites but sometimes items/materials).. Get the items fast cause they disappear fast... Anyway you can do this as many times as you want.. hope this helped