This trick requires healing and may cost some HL. First, choose the character you want to earn Mana for and make them the leader. Then, summon all of your characters and any weapon (preferably a sword). Have the leader throttle all of the summoned characters until they are completely obliterated. Check your status to see how much your Mana has increased. Repeat this as many times as desired. Note: Do not worry about thrashing lower level characters; the higher the level, the more Mana you get for killing them.