I like the idea of an April Fool's Event Quest Chain where Hildibrand takes the player on an amazing quest to find a great blade of legend, only to reveal that it is Excalipoor, which would have the special ability of reducing all damage dealt while Excalipoor is equipped down to 1. Or even have some "Replica Weapons" from all across the Final Fantasy franchise, but as they are replicas, the weapons themselves only do 1 damage and have a high rate of decay, requiring them to be repaired after approximately 10 uses.

This would also allow for players to "pretend" they're using powerful weapons through the "Glamours" System, when they really aren't.