Blitzcrank's E locking onto Invisibles
Blitzcrank
Playing some games against Blitzcrank and often if I play Kha'Zik, Rengar or Evelyn doesn't matter which invisible capable champions. After Blitzcrank autopaths to the target he is trying to Power Fist, even if they go invisible they get knocked up. I'm not saying you go invisible after you get knocked up but before hand. It's as if Blitzcrank still seeks you for about 1 second or less in your stealth and knocks you up.
Might be a bug.