I've pretty much ended up playing this champion whenever I can since I bought him. He's pretty strong in just about any role he's viable in, so I decided I write a general guide for Jarvan.

Hope you like it.

Quints:
Greater Quintessence of Movement Speed: Either these or Greater Quintessence of Desolation will work for top lane Jarvan. I find I prefer these in a harder match-up, but it's really personal preference.
Greater quintessence of Desolation: pretty much bread and butter for a top lane bruiser, though if you find you're not very good at last hitting you can opt for Greater Quintessence of Attack Damage. Again, a lot of this is personal preference, so don't take these options for the only ones.

Marks:
greater mark of desolation: these are generally what I would use for top Jarvan. You could replace these with Greater Mark of Attack Damage, particularly if you find that you are bad at last hitting when playing him top.

Seals:
Greater Seal of Armor: I pretty much take these on all champions at this point and Jarvan is no exception. I wouldn't swap these out for anything else no matter what lane you're in.

Glyphs:
Greater Glyph of Scaling Magic Resist: These are another staple rune I almost never switch out. If you have good reason to believe you'll be top against someone like Vladimir, you could opt for a page with Greater Glyph of Magic Resist instead, but that's the only time I'd switch these out for anything.

Jarvan should generally take 21 points in defense, with nine points in offense.
Offense tree-
I take three in Brute Force and one in Summoner's Wrath , with five, again, in Alacrity and Weapon Expertise .

Defense tree-
For this I take three points each in Hardiness and Resistance with five points into Durability and Veteran's Scars . The other main change in a point in Siege Commander , because I find I end up pushing towers quite a bit and it's pretty decent for that.

Cataclysm > Dragon Strike > Demacian Standard > Golden Aegis

for the most part I max Dragon Strike first early game.

After that it really depends on how the game is going, though I generally max Demacian Standard next, because of its strong utility.

/ : These are generally the best boots to buy on Jarvan, and either will work depending on what you are worried about mitigating in early game trades (physical damage or magic damage/CC)

/ : Both of these items are very good on Jarvan. Generally I find I prefer to build Trinity Force on a tankier Jarvan, and Frozen Mallet on a less tanky one. This may seem slightly counter-intuitive, but there's reasoning behind this. Generally a tankier Jarvan will have more CDR but less damage, which makes Trinity Force a better buy him him because it can be proc-ed easily and will increase his overall damage quite a bit. A more AD heavy Jarvan is less likely to have CDR and will generally want more bulk and damage, making Frozen Mallet a better buy. The only exception to this rule is support Jarvan, who is tanky and builds Frozen Mallet purely for the utility of the slow, though a Trinity Force could be bought if his income is high enough to allow this.

: I personally feel this item is core on any Jarvan who is generally building more AD heavy. It is very strong on him in general, because he has high AD scaling.

Offensive items:
Last Whisper: I find this item becomes very important if you get significantly fed, because the enemies will start to stack armor against you.

Youmuu's Ghostblade: This item can be good on Jarvan because he scales well with CDR and ArPen. He is not a champion who needs to build attack speed very much though (demacian standard gives him quite a lot) and he also tends to scale better with flat AD than he does with critical strike, so this item is extremely situational. I would rather grab an early The Brutalizer > Last Whisper late game most of the time.

Wit's End: This item is perfectly decent on Jarvan, though as I said before he really doesn't need to build attack speed because of Demacian Standard's passive. I've found I prefer to get Maw of Malmortius because of Jarvan's high AD scalings.

Bloodthirster/ Infinity Edge: Generally I find I prefer the former, but the latter will work as well. Jarvan tends to scale better with flat AD over critical strike, but Infinity Edge is a very high AD item, so it can be worth the money when you're very fed.

Wriggle's Lantern: This item is reasonably good on both Jungle and Top Jarvan, though I personally prefer double GP/10 for both. The lifesteal and armor are good against most Top champions/in the jungle and the passive can help if you're bad at last hitting.

Atma's Impaler: This item can be pretty good on Jarvan because it can boost his AD by quite a bit, but I don't generally take it because he rarely needs the passive on it.

Defensive items:
Frozen Heart: I tend to get this on a tankier Jarvan because he scales very well with CDR. It also synergizes pretty well in general if you tend to use Cataclysm on the enemy ADC, because that can completely cripple their ability to deal damage in a fight.

Guardian Angel: This item is generally very good on Jarvan because he scales well with resists and the passive makes it very hard to actually kill him.

Aegis of the Legion: This item is very good on Jarvan, in general. The Aura synergizes well with Demacian Standard and I've found I often buy this item first when I'm jungling him, depending on the enemy team.

Randuin's Omen: This item is also very good on Jarvan and is interchangeable with Frozen Heart in nearly all situations. The active works quite well if you find enemies are constantly flashing (with the spell or skills) out of Cataclysm. It also builds out of Heart of Gold, which is pretty convenient if, like me, you always get one.

Force of Nature: This item can be pretty good if you're building incredibly tanky. The movement speed is good if you're initiating fights quite a bit and the passive boosted health regen makes you nearly impossible to kill.

Warmog's Armor: This item is fine IF you have the defenses to utilize the high health it grants, though I've found I usually prefer Frozen Mallet (unless I already have a Trinity Force).

Utility items:
Shurelya's Battlesong: This item is very good on Jarvan in general. It's a cheap easy way to get CDR and health regen, plus the active is very strong in teamfights and synergizes pretty well with his kit.

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