Illaoi tentacles should always swing on W
When Illaoi uses W, her tentacles swing at target if in range. This means tentacles that are no close enough to the target, don't swing at all.
Here the thing, mobile targets like Zed can easily dodge her W/tentacles and flash back. They may even flash back right next to a tentacle, but because they were not in range of that tentacle when illaoi casted W, the tentacle does nothing.
So what I'm saying is even if the tentacle is not in range, they should always swing in the direction of Illaou W target. either that or Illaoi W should mark them so when they do come in range of a tentacle that did not swing, that tentacle will swing because they are now in range.
I know this might make her op, but it makes sense. These tentacles are a God and should want to smack champs every chance they get.