I was just playing a bot game using Fizz and the Playful/Trickster would sometimes just hit nothing. This only happened 3 times during the whole game, but that doesn't mean it couldn't happen more. I'm really not sure what caused it, the first time it happened was just a group of 3 caster minions, the second time was a group of about 5 caster, 3 melee minions, and a champion, and the third time it happened was during red buff. This is my first time reporting a bug so if you need any more information, just ask. Thanks! (:
Also, the length of the jumps varied. The first time was about a short/mid range jump, the second time was max range, and the third time was a short range jump.