Welcome to my first guide on Jarvan IV - The Exemplar of Demacia.
Let me say as far i've only done a few games with him, and that are my two builds that i figured out.

All in all i got 10+ kills less then 5 deaths and over 20 ***its in games there they didn't surrender.

Pros

Good for singling out a target
Good chaser
Great team ganker
Good initiator
Great for team fights
Can charge through thick walls
Can escape easily from ganks
Can tank single targets
Good Slow with his shield

Cons

Very dependant on quick level 2
Easily focused down (Not the best survivability)
Very mana dependent early game

For both build take Armor Penetration for your Marks and Quintessences.

Damage / Tank:

For Seals take Life per Level
For Glyphes take Magic Resist or Cooldown reduction per Level

Damage:

For Seals take Life per Level
For Glyphes take Cooldown Reduction per Level

Increase of 2% Crit Chance. Good with Phantom Dancer and Crit Runes.
Deacrease the target's armor and magic resist by 10 and also slows if you haven't got your Frozen Mallet yet and Deacreses the damage output of the Carry of the enemys.
3% Cooldown Readuction can sometimes be helpful to escape or to gank.
3% Attack Speed increase
Your attacks pierce 6 of the target's armor.
Increase of 3 attack damage.
Increase your critical strike damage by 10%. Good with Infinity Edge!
Increases your physical and magic damage by 5%.
Increases your magic resist by 6.
Increases your armor by 4.
Why more Armor then Magic Resist? Jarvan already have more armor then magic resist so we need more magic resist in order to tank more.
Increases your total health and mana regeneration by 4%. Good to stay longer on a lane.
Increases your Movement Speed of your Ghost spell by 6% and his duration by 1.5 seconds.

In combination with Demacian Standard and Dragon Strike you can easily escape or initiate a team fight. Also you can catch fleeing champions.
You can reduce the damage output of the damage dealer of the enemys and also catch fleeing champions or flee Crowd controls (CC).
Good to initiate or help an ally with cataclysm and flashing out.

Your passive ability, it removes 10% of your targets CURRENT health upon auto attack every 6 seconds, maxing at 400 extra damage.

Shoots the top of your spear out, hitting all enemies in a line dealing damage and removing a percentage of your enemies armor. If it connects with your Demacian Standard You get pulled towards it, knocking up all enemies in your path.
Shields yourself for a flat amount, increased by the amount of enemy champions around you. Upon activation, slows all enemy champions around you. If you go beneat 300 hp, the shield automatically activates, if it is off CD, and you have enough mana.
Places a battle standard upon targeted location, dealing damage where it hits and increasing all alied champions around it's Attack Speed and Armor.
Passively increases your Attack Speed and armor, stacks with the effect when it is used.
(Ultimate)

You heroically leaps at this target, dealing physical damage and creating a circle of terrain arround them for a few seconds.


First of all skill your Q-Skill (Dragon Strike), at level 2 get your E-Skill (Demacian Standard) at level 4 get your W-Skill (Golden Aegis) to slow the enemy if he flees. Then max your Q-Skill first for more Armor penetration. At level 8,10,12,13 skill up Demacian Standard to initiate with your combo. At least max your W-Skill.

As first item start withand.
Stay on your lane until you can get yourand 1 or even 2.
Afterwards getfor more armor penetration, cd reduction and ad.
Then get yourAS + Crit + your armor penetration runes and Q-Skill and Brutalizer its a nice damage output for ealry beginning mid game.
Will be your following item for more crits.
Then finish yourand afterwards get afor your followingfor more armor penetration.

If you have a heavy tank team then get instandlyafter your Black cleaver in order to kill those.
As one of the last items getfor higher crits and
for ad and lifesteal.
At last finish your.

First buy a
and buywith 1 or 2afterwards.
Then buildto get more ad, armor penetration and cd reduction.
Afterwards finish your Ruby Crystal to.
Then Finish yourfor more AS.
In order to provide fleeing champs get aand build.
For more damage output get aand.
At last item getfor a Magic Team or afor a Normal Damage Team.

For your Tank / Damage build you cant get instead of your Yoummuus Ghostblade another Magic Resistance or Armor Item.

Heavy Physical Team:

Good against physical champions with less or no lifesteal.
Perfect against high physical and attack speed champions with slowing down their attack speed.
Nearly the same like your W-Skill. An extra slow for your enemys with life and armor. Dont forget do activate it if you have it!


Heavy Magical Team:

This item gives you life, magic resist and mana, and block every 30seconds a spell of your enemy. In my opinion the best choice in team fights.
If you have a pure magical team as opponent then get Force of Nature and Banshees Veil together. Life reg and the highest magic resistance in game with and passive life reg is just awesome.
Can save your life and give you a shield like your W-Skill for keeping you alive.
In my opinion not the best item in combination with Jarvan. You dont need AP, but its the item with the second highest magic resistance and its a great help for your caster in teamfights and teamfights are the main aspect of winning a game!


Physical and Magical Team: You got to examine if the team got 2 physical or 3 or 2 magican or 3 and in that way you can choose your items from ahead.

Coming Soon.

All in all I can say Jarvan IV is one of the champions who are really great in early, mid and late game. He's a good harasser with his Q-Spell and good initiator with Q-Skill + E-Skill followed by his Ultimate.
Have fun with him.