When 
uses unstoppable force, if 
times it right, he can avoid the knock-up by using playful trickster.
So the bug will go off something like this... -malphite ults, and the sound for hitting something goes off, therefore fizz is knockup -fizz uses playful trickster and avoids the knockup and the damage from malphite ult.
Ether the sound of malphite ult is buged or fizz is actually dodging malphite ult.
fizz jump is like yasuo's wall, for example u can see nid spear hit yasuo but he puts wall right before it and it blocks it
according to your low elo rank, fizz dodged it
Fizz's E makes him untargetable.
Malphite's ultimate cannot hit someone who is untargetable.
This is the intended behaviour.
I have over 1k games in normal games on this account, in addition to knowing exactly what move fizz used so its sad to see that everyone thinks I have never played or at least played against a fizz before.
What i'm referring to is the difference in sound that makes when he hits something vs when his ult does not even hit a lane minion.
