Quote Originally Posted by Wolf Kanno View Post
I don't remember them saying that Ultimecia failed with Time Compression rather it began from the past and moved towards the future since she cast the spell in the past. I always thought your party was attacking her before the spell was completed as opposed to after it failed. Her final form alone is actually absorbing time as you battle and you simply defeat her before it finishes. This was at least how I interpreted it, I'm not quite there yet in my current playthrough.

I do like the theory of Omega Weapon existing due to Time Compression as opposed to being some other all powerful Weapon.
The info we get from Odine and Laguna indicates that once Ulti gets back to the past, she will start casting Time Compression. Squall and company use the merging of past, present, and future to reach Ultimecia. If time hadn't begun to compress, they would never have been able to reach Ultimecia where she dwells in the future. We manipulated her Time Compression to reach a point where we could attack her. So she definitely started casting the spell. Either it failed, or it didn't wipe out everyone else. Either way, it wasn't enough to stop Omega.

Her "absorb all time" spell might have beaten Omega, but I think he could have destroyed her before she finished it, if they were actually fighting. She clearly needs something to reduce her casting time.