Final Fantasy Crystal Chronicles synopsis

When a meteor falls from the sky and shatters the great crystal, lacing the land with its shards and smothering the countryside in a blanket of poisonous miasma, people are forced to build towns around the crystals to protect themselves from the abounding monsters and send out travellers to collect drops of myrrh and recharge the crystal's protective energies. But this endless cycle will have to end sometime... what is the origin of the meteor? And why are the villagers perpetually losing their dearest memories?