1 Pros/ Cons
2 Early game
3 Mid game
4 Late game
5 Runes
6 Summoner's Spells
7 Summary

Great handling of dmg
Good mob killer
One of the best team players out there
Awesome jump+knock combo
Aoe slow+shield
Great support for carry and all the team with standard
Great Hybrid Tank/dps at once
Good survivality

Cons
At early game low movment
Not enough mana at early/mid game if don't get golem buff
without buying items for attack speed people always can ks you
No one of enemy team will like you xD

First we buy doran's shield with this build and item u have some like 700 hp if u chose some with can cc with you you can easy first blood (prefer xin zhao, nunu or fiddle). if you came too slow, try to find hidden enemies with dragon strike. Jarvan can be also put in mid.If enemy is greedy and try to kill you so fast exhaust them and dragon strike him (with standar if u have) then ghost if u need but preffer to keep ghost for run if enemey run to turret but are for one hit. Also if u have problems with ranged try to keep turret and lvl fast to 6 lvl, if u have low hp enemy probably will try to kill you, use cataclysm and kill him/them with turret. there is another option, you teammate can tank you (only if you have low hp) cataclysm them and you have kill :)

Sometimes if u teammate are melee too u probably will have problem with ranged/ 2 rangeds well there are only two options, you have to hide or you friend and one go like bait, another ano go from behind then use cataclysm, standar and dragon strike and just one enemy left, you can run then with ghost to him , or away from him (if he fedded or you don't have enough hp)if u run to he use exhaust and for sure u got kill him with your teammate. Also u can use cataclysm then fiddle use crownstrom and they too got owned. Be carefull with using standar enemys can use flash, then u need to put Demacian standar then dragon strike and use exhaust. Somehow then can be mass pvp on mid this build means you can do big dps but also tank if you trust them say them to hide or trap them then cataclysm ( xin zhao cun run into it, nunu can ultimate like fiddle) Good Luck

If u got all items that i put, and enemy aren't feeded you can easily action like iwrote in mid game, Trap or teamwork aoe(area of effect) which means cataclysm + something combinations of aoe or ulti skills. Don't be afraid of turrets if u have to just use dragon strike on enemy or one hit Golden Aegis can absorb 2-3 hits of turrets hit, Sometimes good choice is too deal with enemys when your team will be destroying inhibilator, With buff brom baron they will ned 3+ people to kill you (if not feeded) Good luck with playing.

Greater Mark of Desolation - I think it's the best choice if u want to kill someone, not just tank and it's the best choice for all melee
Greater seal of Vitality - best choice if u buy Atma's implarer and for sure for tank. Also u can choice Greater seal of Evasion as all tank does.
Greater Glyph of focus - jarvan is auto ataker but really bassed on dragon strike and standar, so with cd i make easy way to cc
Greater Quintessence of Desolation - also like mark

Exhaust best choice, if u need to run away, stop some dmg or stop from running you must have this summoner skill, with Demacian Standard and Dragon strike no one can run away from you.

Ghost- at eraly game this build show to buy Doran's shield to have better stats so if you have to run away or to him, with Demacian Standard and dragon strike no one can run away from you. At mid/late game you can rush into you're enemies to stop them because u team have to run with Golden Aegis then Ghost and Demacian standard and dragon strike combo you can always run away.

Flash it's good skill to mid/late game after cataclysm u can run with flash and stop you're enemies. Also good to early game for running away.

Ignite it's not the best skill but if u have problem with overhit u can chose it as well.

Jarvan IV is one of th best Support for carry and killer, but like all have also cons item cost some so u have long way to bought them, If enemy begin feeded and you don't get any kill you will have diffcult way to win. With good teammates and thinking you can win all battles without dying so much. At early mid game buy some mana potions