The Best ult in LoL is...?

I want to know what the people think is the best ult in LoL. I dont mean just based on damage but that is still acceptable.

My Vote goes to . Global ult that reduces vision of the entire enemy team but also a long range and super strong initiate. Nocturnes ult can really screw over a team once they cannot communicate or see each other within a short distance. This opens up so many chances to make a play without the other team even knowing. It is also completely immune to CC during the duration of his flight. -Fun Fact- Nocturnes ult has priority over every other any other source that grants vision, meaning if Twisted fate ults at the same time Nocturne does, The vision granted by Twisted fate is cancelled.