As posted on NeoGAF, a sidequest has been discovered in Final Fantasy IX 13 years after its initial release. While it’s nothing new for easter eggs and hidden areas to be discovered several years after a game’s release, it isn’t often that an entire quest flies under the radar for so long. If you still haven’t played the game yet, read no farther, as the steps to trigger the sidequest may spoil a bit of the game otherwise.
The steps that trigger this quest explain why it went undetected for so long. To start, if you go to the Tantalus hideout at the beginning of the fourth disc, you will find Zenero and Benero, who are wondering where Marcus and Cinna are. This is the beginning of the side quest, but most people passed it by without a second glance.
After you have spoken with Zenero and Benero, you need to head to Memoria and proceed until you either watch a cut-scene or end up fighting a boss. After you have done this, you need to head back to the hideout, where you will find Genero wondering where Benero and Zenero are.
From here, the process is simple. You simply repeat the above process seven more times. As you repeat the process, you will find a new member of the family in the hideout. Upon talking to the final member of the family, a chest appears inside the hideout. The quest restarts if you come back after obtaining the chest, but there simply are not enough events that move the quest forward to allow you to complete it twice.
Credit for locating this new quest goes to The_Kusabi_, and credit for the video belongs to GarlandTheGreat. Are there any other hidden quests in Final Fantasy IX?