Jarvan IV is a little ridiculous right now. Here's a few reasons why.

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I know that this is going to seem rather weird during all the discussion of Nemesis draft, shitty ranked placements, and Lee Sin hate, but please hear me out.

Jarvan IV is pretty broken right now.

I'm not sure that I could give a specific reason why he became broken when he wasn't a few patches ago. What I'd like to do, though, is discuss both my rationale for saying he's broken and go over the negative effects that someone like Jarvan being broken has on the game.

##Statistics Don't Lie

The only champion more statistically fearsome than Jarvan IV on patch 5.2 was Ahri. (Source: http://pryorability.blogspot.com/2015/02/league-of-legends-tier-list-patch-52.html) After Jarvan and Ahri, the next two champions, while certainly very strong, fall off extremely hard. But then Ahri got nerfed in 5.3, while Jarvan IV was left completely untouched.

Balancing by win and pick rate does have a somewhat poor reputation on these forums. Yes, many champions who we think are extremely strong or extremely annoying to deal with have low win rates, like Lee Sin. But while people can make a very convincing argument that Lee Sin takes skill to play well (artificially decreasing his win rate), nobody can really argue with any credibility that Jarvan is a hard champion. The only thing that makes Jarvan difficult is not screwing your team with his ult, but that's much less of a big deal now that you can cancel his ult on demand.

##Team Synergy

There is never a BAD time to pick Jarvan. This is because Jarvan is literally the prototypical jungler at this point. Strong early ganks with hard CC? Check. Steroids/free damage for clearing? Check. Can build full AD to snowball harder if he's fed, but doesn't suffer at all in a full tank build? Check. Jarvan provides everything to your team that you could ever want a jungler to provide. That would be alright if he was a champion who did everything kind of OK but wasn't outstanding or even above average at anything. But he's not. He's just...what you want your jungler to look like, regardless of your team comp. Outside of his status as one of the best ganking junglers, every playstyle wants him. Poke/Siege wants him for his E steroid and Q poke. AoE teams want him because he's Jarvan. Late-game focused scaling teams want him because he's incredible at whatever you build him into, tank or fighter. Assassin comps want him because in midgame having J4 is like having a second Zed.

There's something to be said for seeing how the Gnar changes, small as they are, affect his viability, but I don't think they'll hurt him at all. Jarvan doesn't need Gnar in particular because any champion with an AoE wombo functions well alongside J4; on the other hand, the shape of Jarvan's ult wall made it nearly impossible for Gnar to miss a multi-man stun, making him function much better with Jarvan than he did alone.

##Variety Killer

Jarvan is too good at too many things. He's a generic bruiser from the "giant ball of stats" era of melee champion design. So, naturally, he's a jack of all trades who for a long time did basically everything at an average level, but was never really a great pick. Obviously, that's changed now. Jarvan is so good at everything you want a jungler to do that no specialist junglers can exist while he's a strong pick. When junglers entirely focused around ganking gank only a little better than Jarvan does, while Jarvan does literally every other aspect of the game just as well or better than they do, there is no reason to play anyone other than Jarvan unless he's banned.

To better illustrate this point, let's look at a specific class of champion that's pushed out by J4.

So long as Jarvan IV is a strong champion, there is no reason to play tank junglers. I wish that I could say this wasn't the case. But one of Jarvan IV's biggest strengths is his ability to hard engage for his team. This puts him directly in the middle of the niche of tank junglers, who often lack the damage of bruisers early but make up for it with their large amounts of CC and hard engage capability. Jarvan has both the burst and sustained damage of a bruiser and the CC and engage of a tank. Why would you even consider giving up that early game damage to pick someone like Sejuani or Nautilus when you could just pick Jarvan who deals twice as much damage early game while being able to build full tank just as well as they can late game?

Essentially, Jarvan needs to get hit HARD in 5.4. He simply has too much of everything, being a melee champion made in the days when every melee champion had to have too much of everything. He is by far the dominant jungler statistically, and his mere existence makes many other junglers unpickable. He has no thematic identity other than "manly man who takes a long time to die and kills you quickly".

Riot plz.

EDIT: If everyone else is underpowered to J4, that's literally the same thing as J4 being overpowered. But it's always easier to nerf one champion then it is to buff literally every other jungler.