The actual problem with Fizz
Riot made a lot of changes to 
. The old one was extremely broken. His Q did more damage and his W had Griveous Wounds. While his ultimate didn't had an amplification debuff (which is essentialy an in-built Deathfire Grasp), Fizz didn't really needed the ult to kill an squishy target, just jumping on them with E + Q + activated W was often enough. Once the old Fizz built Lich Bane, it was game over for his lane opponent; unless he was extremely far behind, he would beat you and become fed.
Then Riot nerfed his Q damage and changed his W so that the % missing HP damage was no longer a passive "over time", but an active on-hit effect. Also, his ult was changed to amplify the damage against champions who are hit by it. This was a hit to his AP build, but a fantastic buff to his AD build.
Once deemed as a troll build, AD Fizz was discovered to be strong, and with the on-hit % missing HP damage, he was actually broken; he could purchase a Blade of the Ruined King and a Trinity Force, then build tank from that. You couldn't kill him but he could kill you. He was like an Irelia/Jax that had far more damage and mobility.
Then Riot changed Fizz's W back to what it once was, without the Griveous Wounds part. The rest of his kit was unchanged, so this essentially means that Fizz is again what he used to be before all changes, except that he is now more reliant on his ultimate to kill anyone.
This indeed made Fizz healthier, but on my opinion Fizz is still not healthy enough. He is still frustrating to go against, and can snowball (not as hard as before, but he can still snowball).
On my opinion the reason for all the problems with Fizz is his E (Playful/Trickster). This skill is the sole reason why Fizz is so frustrating to play against and is a nightmare if fed. It's a mobility spell with a very low cooldown that has a potential soft CC and makes Fizz untargetable. This allows him to avoid any damage and CC thrown at him. With the many point-and-click abilities being changed to become skillshots, countering Fizz is becoming harder and harder, since he can just dodge anything.
The only downside of Playful/Trickster is its absurdly high mana cost. However, this is not much of a problem once Fizz gets 
and/or 
.
"Playful/Trickster" is a skill without any counterplay. Let's compare it with the mobility/safety spell from another assassin:
Her shroud is her safety spell. It allows her to become "untargetable" to her target, but not truly untargetable. She can still be hit with AoE abilities. Also, a single pink ward means that now you can see her and target her again. Also, she needs her ult to be able to dash to her enemies.
Fizz cannot become invisible, but neither pink wards, nor any other item for that matter, will allow you to counter Fizz's untargetability. Also, it offers mobility just from the start.
On my opinion this spell is very overloaded and it is a big part of why Fizz is a toxic champion. I know that every assassin should have an safety spell, but Fizz's Playful Trickster offers too much safety. Especially since it's an untargetability spell combined with a dash, and Fizz already has a dash on his Q.
If at least it had an higher cooldown (a lot higher than it currently is), Fizz would not probably be so much of a problem. There are other champions who can become untargetable but on a much healthier way, lets take an example: 
. Vladimir's Sanguine Pool has a very high cooldown, even with 40% cooldown reduction. It costs him an huge portion of his health pool, and do not allow him to dash through walls. It is also never maxed until late game, and on top of that, its damage is mediocre. Sanguine Pool's only advantage over Playful/Trickster is the fact that it costs no mana. However, the health cost is arguably worse, especially early game, since it lowers Vladimir's survivability.
I don't know why Riot refuses to change this spell. They say that they don't want to change this spell because it's Fizz's iconic ability, but guess what? Riftwalk was 
's iconic ability. Riot refused to change this spell, and instead they made lots of unecessary changes, until they recognized that it was Riftwalk that made Kassadin so strong. Then, they nerfed it; but it was too late, as the rest of Kassadin's kit was already nerfed and this made Kassadin weak. I wonder if the same thing will happen with Fizz.
Riot could replace the untargetability with massive damage reduction and/or tenacity. This way, Fizz could still use this ability as a means to win trades and become safe, but he could no longer just dodge anything. Heck, just increasing this ability's cooldown would already be a great change.
The way that it is currently, Fizz is too safe, he has two dashes, and untargetability, and with the AP build, he can build 
to become even more safe during teamfights.
Who agrees with me?
