to get mog, you go back to narshe. go up the stairs on the right side and you will find two houses, up and down. go to the down one and Lone Wolf, the infamous pickpocket, will yell something. talk to him and he'll run. follow him north and he'll say that you're persistant or something. keep folowing, he'll go into the mines. go up to the place where the great battle with Kefka was, where you had to protect Banan against the soldiers. go to the frozen esper Tritoch. he'll hold mog hostage and say that if you move he'll kill him. so..................dont move. then mog will sprint and both of them will hang from the cliff. now, the moment of choice...tylenol or advil? if you talk Lone Wolf, you'll get the Gold Hairpin which halves your MP consumption, but then both MOg and Lone Wolf will fall and die. If you talk to Mog, he'll join your party.
then, in the world of ruin, go to the moogle mines through the place where locke first saved terra and you'll find him in the moogle mines. once he rejoins your party, you'll also find a Moogle Charm on the wall behind him (possibly the best relic in the game). the Great Moogle Charm will ensure that you will not encounter any battles except for bosses and "monster in the chest".
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