The side quest to obtain Excalibur II is the most difficult side quest in the game. It may even be one of the most difficult in the entire Final Fantasy series!
The reward for successfully completing it is Excalibur II, the most powerful weapon in the game, which can be used by Steiner. It can be obtained in Memoria in the Gate to Space room by searching to the right of the main pillage. The difficulty is that you must reach the Gate to Space with less than 12 hours go gameplay (as registered in the menu screen as 11:59:00). It’s a race against time!
There are a few key strategies which need to be employed in order to reach the hidden sword in time:
1) You have to be able to speed through each of the areas of the game. This guide can help, but you will need to be intimately familiar with some of the areas in order to travel through them quickly enough.
2) Skipping all optional content including Active Time Events (ATEs) and Full Motion Videos (FMVs). You can skip videos by opening the PlayStation cover or ejecting the disc from a PlayStation 2 (not an option if you are playing the Steam or iOS version).
3) Save your game at various points and repeat parts of the game until you get the time own to an absolutely minimum.
Pausing does not stop the time from ticking. Just reset as you need to an rush through as fast as possible.