I'm hard pressed to think of anyone more blatantly overpowered than Orlandu from FF Tactics. Let's look at the facts:
1.) He's a storyline character. No additional effort must be made to find him AT ALL.
2.) He comes equipped with one of the most powerful swords in the game.
3.) He renders three whole characters almost completely redundant (Granted, one only is in your party temporarily) and stops shy of completely eclipsing the other two purely because they are female, and can equip Chantage, and he cannot. Hell, you even get one AFTER him.
4.) Most importantly, he enters your party, and pretty much every subsequent battle becomes all but completely trivial. His stats, the effect, and power level of his attacks...granted, one should expect it when one earns the moniker of "Thundergod Cid" but yeesh!