The Manticore is a tough enemy, so it is best to have characters with high Defense, such as Knights. Constant healing will be needed, so the player should make sure to have some higher level White Magic available.
The player can also change everyone's Jobs to Summoner and repeatedly use Titan. It will not work if the opening move is Aqua Breath or Frost, but the player can reload and try again.
A strategy for a weak or underleveled team is to have a Time Mage that can use the spell Stop on it every turn. Thusly, the Manticore will be unable to attack at all, allowing the player to do just about anything with this fight. Another strategy is to use the Blue Magic spell Death Claw, which will reduce the Manticore's HP to single digits, leaving it vulnerable to dying from another attack.