If Fiddle was the start his ultimate (the period before the teleport) and Blitz or Nautilus used a Q on him, would it cancel Fiddle's ultimate, using the cooldown?
11 Answer
Once Fiddlesticks has finished casting Crowstorm, has teleported and the spell effect has started, nothing can stop it - you're screwed.
However, if you can grab Fiddle while he's channelling, before the spell actually goes off, you will cancel his ultimate. Silencing him during this channel also works.
5