MLP FiM My Little Pony Friendship is Magic
S03E02 S03 E02 Season 3 Episode 02 The Crystal Empire Part 2
Spike & Twilight Sparkle - Spike's worst fear

Spike - Ponyville?! Well, how did I get... no! I don't wanna go! Please, Twilight, don't leave me!
Twilight Sparkle - King Sombra's dark magic. A doorway that leads to your worst fear.
Spike - We were home... you told me you didn't need me any more. You were sending me away...
Twilight Sparkle - A fear that will never come to pass. I'm never gonna send you away.