Jax Build Guide by PH45
[9.18] PH45's In-depth guide to Jax, the Grandmaster at armsBy PH45 | Updated on September 14, 2019
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Choose Champion Build:
Runes: Read the notes
+10% Attack Speed
+9 Adaptive (5.4 AD or 9 AP)
+10% Attack Speed
+9 Adaptive (5.4 AD or 9 AP)
+10% Attack Speed
+9 Adaptive (5.4 AD or 9 AP)
Ability Order Max vs melees and usual matchups
Threats & Synergies
When facing Cho'Gath in lane, pay attention to his position when he uses Vorpal Spikes. Don't get hit by the spikes to avoid the slow and if he fights you with them make sure to dodge the damage with your Counter Strike. Key here is to dodge his Rupture and just all in him after that since he loses to you after that unless you are miles behind him (which shouldn't happen). Just be careful if you are low HP as he can quickly delete you with his Feast. Overall one of the easier matchups for Jax.
While playing against Illaoi it's important to dodge her Test of Spirit. After she misses that you are free to trade with her as she misses a good portion of her damage when she can't utilize the spirit from it. If she ults and you know you can't finish her at that moment Q away as she heals for a good amount when she deals damage in her ult. If you are having trouble with her healing buy a Bramble Vest or a Executioner's Calling, although I'd suggest not finishing it into a Mortal Reminder since Armor Penetration isn't really worth on Jax, especially since we are running Conqueror. Rather ask your ADC to build one possibly.
The reworked Aatrox is a lane bully, especially to melees. He works as juggernaut now and he is actually pretty oppressive vs melees. Important thing in this matchup is to dodge his key points of his Q. It is also important to walk out of his W from the side before it retracts you to the middle as it basically guarantees him a key area hit on his Q if you stay in the area. Trade while he uses the first 2 procs and then quickly jump out before the 3rd one lands. He heals everything back up though over time pretty quick so junglers help is appreciated. Tabi and bramble are good items to get but mobility helps out a lot and most often after getting Phage your kill pressure on him rises a lot. Late game you outscale. If he misses his Infernal Chains you can try to all in him. Just dance around his Q procs as they chunk you a lot.
The reworked Akali can prove to be quite annoying but she got pretty gutted so she isn't that often seen anymore. Fight her when her shroud is down but care about her burst. Also try to not eat her Q for free since she will chunk you down fast with those + her empowered auto afterwards.
Can be a difficult lane. Important thing is to block his W with your E and don't let him get his passive to 5 stacks on you. If you can't run out of his Q circle Q on him so you will be in the inner ring, denying him his heal. You outscale him quite well so just don't let him get ahead and you should win him. Early tabis also help quite a lot in this matchup.
Avoid his cleavers as they slow you quite a bit aswell as deal hefty amount of damage. You have low kill pressure on him once he get's a few items. Blade of the ruined king is good against him.
I find Fiora quite an annoying champion to lane against, if she knows what she is doing there isn't a huge window for you to win the lane. Be careful when using your E since if she ripostes it you will pretty much die to her as she stuns you with it. It is best for you to try and upkeep your E for the maximum duration as most Fioras will try to predict you to use your E's stun earlier than the end of the duration. If the vital is in a bad spot walk out of her vision so the vital reappears in a different spot. If she ults and you can't kill her quickly ward jump out since she deals true damage aswell as heals herself for quite a bit. Tabis are good in this matchup aswell.
Really passive lane for most part as GP tends to play pretty safe early on. His Q poke can be annoying so you can start Dorans shield + pot if you want to negate some of that poke. Try to bait out his oranges and when it's on cooldown then all in him. Maxing Q can help in this matchup, but it will lower your overall DPS.
Can be difficult as he just runs in and Q's you and then runs away. If you get him low he will just stick under tower and heal back with his passive. Later on you will be more useful than he is so just try to go even with him and farm if he doesn't make a mistake and let you kill him. Careful if he has marked you as villain as his ult will deal true damage then. If he engages you and spins with E just jump away since he will remove some of your armor if you stick in his spin for long enough.
You can't really kill him easily as he will just jump away if you engage on him. He will just poke you with his Q and his W's damage. Get tabis and after he uses his jump then engage on him while it's on cooldown.
Really annoying since if you try to jump on him he will just E on you and negate your jump aswell as stun you briefly so he can proc his TDL and run away. Just farm and try not to fall for his bait's as he can set up for ganks quite well with his E and ult.
Dodge her stun blade and be careful of her Q'ing around. Otherwise just smack her like any other melee matchup.
One of the toughest matchups for Jax. He will poke you out of lane in the early levels of the game and if you try to all in him he will just E you out of your stun range if you jump on him and even if you don't you dont necessarily have the time to jump on him. Build tabis and ask your jungler for ganks if you think you can kill him. Farm as much as you can as this is a lane that is very difficult to win until later points of the game.
This matchup changed with the Pantheon rework. His Q poke is less reliable now and his passive no longer blocks autos. Be careful about his empowered W and also when he uses his E, Q behind him to be able to deal damage to him. You still outscale him so you should be fine if you don't int the lane.
Shouldn't be too big of an issue but he has quite a bit of damage early on so don't underestimate him. His all in is very strong so if he jumps on you with his ult just jump out of it with wardhop or onto a minion.
He is really annoying and slippery. Will poke you early a lot so getting some sustain is a good idea. If you try to jump on him he will just stun you and E away. If his E is on cooldown and you are confident he can't kill you all in him then. Care for jungle ganks as his ult sets up ganks quite well.
Dodge his W's procs with E and you should do good. Avoid getting hit by his Q and you should win all ins against him. Careful however since he gets courage quickly when hes attacking a champion so back off if you are low hp since he get's quite a lot of hp back just by attacking you a couple of times.
Annoying to lane against pre-6 but after that you can get some damage onto her with your Q + 3rd auto proc off your R. Most of the time if you jump on her she will just W you onto place and E or run away. Careful of her ult as she can get quite a bit of damage onto you while you are ccd.
Maybe one of the most annoying lanes you can face. He is weak in early levels so try to force him out early. If you try to trade with him after 3 he will just E and you probably can't finish one auto attack off before he runs out of range. He stacks armor too so your autoattacks won't do much damage to him. If he E's just jump away with Q so you wont take more damage from him. Beware at 6 since his ult is really strong cc that can enable the enemy jungler to get a free kill on you if you aren't careful. Gunblade is good against him since it gives you sustain and both magic and attack damage.
Can be semi-difficult to kill as he has built in sustain and he can just Q you if you try to jump on him. After 6 and with a couple items he shouldn't be a problem to you though. Bork is good buy against him.
Try to make use of his weak early game. All in him at level 1 with e and force him away. If you play smart you can win this matchup but later on his W's attack speed and movespeed slow will make it hard for you to kill him. Ask your jungler for a gank if he pushes as he has no escapes besides his summoners.
CC monster. You will have a hard time killing him if he plays the lane right. After a couple items you can kill him but it is incredibly easy for him to setup ganks with his cc full kit.
Don't let him get too many E's on to you as it deals true damage. He has quite a good sustain with his W so careful for that. He also gets more attackspeed the lower his HP gets so be careful of that.
Her W will deny your jump so try to bait it out and jump on her when it's ended. She will get quite tanky and still deal good amount of damage so she might be hard to deal with especially early with her shield and stun. Try not to stand near walls as she can stun you with her E if she gets you against the wall.
Annoying poke and will just E away if you jump on her. Cloth + 4 pot and ask jungler for ganks. Later on you can burst her down but early you should not have too big of a chance on killing her.
Lane bully, nothing else. Be careful at early levels since if he has fury built up his w and q deal a lot of damage. Block his W with E and you should win every trade. After 6 you should have quite an easy time against him with poking him with your ult + W proc. Tabis recommended in this matchup.
Abuse her cooldowns. She can burst you quite quickly. At level 6 if you are low be careful as she can quickly catch up to you and just ult you to death. Very slippery so hard to kill early.
He can just force you out of lane with his flamespitter and harpoons. Get some magic resist and after 6 you can just auto minions twice, then Q onto rumble and auto + W for a lot of burst damage. Merc treads are a solid in this matchup.
Can be difficult to kill since he can block autoattacks aswell. Gets quite tanky but he shouldnt have kill pressure on you unless he sets up an gank with his E. He will roam after 6 with his ult so be prepare to teleport where he is going or to stop it with your stun.
You can try to fight him level 1 by stacking your attack speed and Qing on him. Can be really annoying until about level 11 when you have some items you can actually kill him despite him being Teemo. Usually Teemos want to cheese so they run ignite so be careful as his poison + ignite can kill you really easily in early levels. Get some magic resists, Adaptive Help is a super good item vs Teemo. Later on you will be much more useful than Teemo as Teemo is mainly a lane bully champ rather than late game teamfighter.
Block his Q with your E and be careful when he ults you as it removes some of your resists and drains your hp over time. Don't give him lead in lane and you should win him. If he gets ahead he will become too tanky for you to deal with until later on if you can catch up.
Don't get cheesed early by his RNG crits. Save your Q for re-engaging him after he spins away.
Sustain is good in this lane, get some mr and vamp scepter and just farm up and you can kill him later on. You have to bait his pool though or he will just dodge your stun with it. While laning try to avoid getting hit by his strong Q poke since it deals quite hefty amount of damage. Stay behind minions so his E can't hit you.
Volibear shouldn't be too big of an issue to you. He can be hard to finish off though since his Majestic Roar knocks back champions now and also his passive Chosen of the Storm can save him from death. Your Counter Strike blocks his Rolling Thunder so make sure to make good use of that in lane. Care of his W's damage though as it can hurt a lot when you are low HP.
Very slippery so you should not try to fight him too much early. After level 6 you should be able to outrade him with your Q + passive R proc. Tabis are good against him aswell.
Can be annoying, don't chase him unless you are confident you can kill him. Blade of the ruined king is a great buy against him. Rush it and run him down. Some run ignite though so be careful of that as he deals surprising amounts of damage with or without it.
Dodge his Q and you should be fine. Gets pretty tanky so might be hard to kill until you get some items. After he dies run away as his passive form deals quite a lot of damage.
Get early mercury treads and try not to get rooted by his W. After level 6 you should be able to beat him in trades if you don't get hit by his W. He has good sustain though so prepare to get forced out of lane, jungler ganks are pretty important in this lane as it can be difficult to beat him 1v1.
Play careful as he has quite a bit of burst damage. Block his Q with your E and wait to stun him after he comes out of his stealth. At level 6 he will probably try to all in you so care for that. Tabis are important in this lane.
Seen rarely in top lane. Can be tricky to deal with since she can push you away with her E if you try to jump on her or stun her. Best advice is to get tabis and after she has used her E then Q on her and chip her bit by bit. Careful at level 6 as she can stealth and move away from your stun and just throw you to a nearby wall and stun you.
Get's quite tanky and has somewhat of an advantage in lane with his forging items. After a certain point you won't probably be able to kill him since he get's tanky but you can try to shove him under his tower. Make sure to save your E for his W+auto combo.
Relies on autoattacking a lot, so you should be fine if you manage to block her Q, especially the true damage one. She can be difficult to gank if she has her E up since she can just hop over walls with it so if your jungler is coming for a gank try to bait her into using it.
Deals a good amount of damage early and can be hard to duel early as well due to his passive negating your W damage. Get merc treads and farm up and fight him if he misses his Q and W.
Reworked Kayle doesn't have a huge threat level due to her really weak early game. Care for her empowered E auto and try to not trade when she has lowered your resistances with her Q. Smash her early so she won't get to her powerful late-game state since at that point you are pretty screwed.
Runes: Basic PTA
+10% Attack Speed
+9 Adaptive (5.4 AD or 9 AP)
+10% Attack Speed
+9 Adaptive (5.4 AD or 9 AP)
+10% Attack Speed
+9 Adaptive (5.4 AD or 9 AP)
Champion Build Guide
Hello, I'm PH45, and this is my Jax Guide.
My real name is Patrik, but you can call me either way. I am a long time League of Legends player (started back in Season 1). I'm a top lane main, and I picked up Jax as my main champion back in Season 5 and have played him mostly ever since. I reached Diamond 5 in Season 7, Diamond 3 53 LP in Season 8. I have about 2 million mastery points on Jax when adding up all of my accounts so I would say I have mastered him quite well.
My EUW OP.GG
I also got multiple other accounts but right now I'm switching between accounts and don't have a clear ''main account''.
Check out my YouTube channel where I occasionally post League related videos!
Now on to Jax. Jax is a bruiser style champion, who can really be very diverse with his builds and playstyles. You can play him as a splitpusher and duel almost anyone late game, or you can build him more tanky and peel for your carries, or just go all out and build him as a burster (although not recommended most of the time). Jax is a great champion to pickup as he isn't necessarily the most complex champion mechanics wise, but rather requires matchup knowledge. Knowing where to be and what to do at the right time as Jax is the key to utilizing him to his fullest potential.
Flash: Best summoner spell in the game. Some like Ghost but I much more prefer Flash for capability of getting over walls or quickly getting in range with Leap Strike.
Ignite: I wouldn't really bother taking Ignite on Jax. Sure it can help you score early kills but the spell scales so badly compared to Teleport it's just not worth it. Especially if you lose lane hard it will feel extremely bad to have this summoner spell when you could've just had Teleport to help you out in a losing matchup/bad lane phase.
Teleport: After the Ignite nerf, I find Teleport again to be the more appealing choice as the second summoner spell. Most of the time it enables you to splitpush and teleport to teamfights if you aren't near the fight when it breaks out. It can also help you in tough matchups where you have to back a lot early but main focus with Teleport is to have map pressure instead of getting back to lane to catch that one wave. Just be careful when using it since you can't cancel the teleport anymore so choose wisely when to use it.
Smite is mandatory for jungling so if you are jungling take it. Often I like to take Stalker's Blade when I'm jungling as Jax for added stickiness but occasionally you might need Skirmisher's Sabre for added dueling power vs certain champion/if they get fed.
+ Excellent duelist
+ Can fight almost anyone late game
+ Extremely strong late game
+ Great splitpusher
+ Has a built-in escape with ward + Q
+ Has an auto-attack reset
+ Gets naturally tanky in fights when using R as it gives you a good amount of resists
Jax is a very strong fighter once he picks up a couple items, and in late game he can be a monster in the right hands.
- Can be shut down with CC
- Hard to get back in the game if behind
- Requires matchup knowledge
- Has some difficult matchups
- Can sometimes struggle with teamfights
|Precision benefits Jax well, it offers him tools to deal with tanks and overall a nice set of runes.|
As the keystone of choice I have picked Conqueror, other choice is Press the Attack. Conqueror is a great rune choice for Jax, although the previous version was far easier to make use of. Damaging abilities and attacks grant 2-6 adaptive force for 8 seconds on melee (2 seconds for ranged) and it stacks up to 5 times. At max stacks it also converts 8% of your dealt damage to champions as true damage, and you heal for that amount also. For jungling Press the Attack is the superior choice (although Conqueror might actually work in jg now, in top lane Conqueror is the better keystone right now.
Press the Attack gives you more damage towards the target you have attacked with 3 consecutive basic attacks and it also increases damage to them from all sources for 6 seconds. Jax can pretty reliably proc Press the Attack and gets great benefit from using it, but I think Conqueror is the better keystone on top lane right now, Press the Attack is better suited for jungling.
|Next one on the list is Triumph. It replaced Dangerous Game and can save you in a clutch situation or just grant you some HP back in a intense teamfight.|
|Next are the Legend tier runes, from which all are fine really. I have started to like Legend: Bloodline, especially after the buff for it's late game. Legend: Alacrity is an alright choice due to the extra attack speed but Legend: Tenacity helps a lot vs high CC comps, or even vs lower CC comps it still really valuable. Your choice you should alter depending on your match. If your opponents have a lot of CC or lockdown you are afraid of pickup the tenacity one. If you aren't afraid of that then you can take the Alacrity one and gain permanent attack speed with it or take Legend: Bloodline and gain sustain since my builds usually don't include lifesteal.|
|Lastly from the Precision tree we have either Coup de Grace or Last Stand. I like Last Stand on Jax since you'll be in the middle of the fight most of the time so you'll take damage anyways and deal more damage with it. With Coup de Grace your targets melt faster when you get them below 40% HP, which Jax can do relatively easily when snowballing. Both are fine but personally at this moment, I prefer Last Stand.|
|Inspiration is still fine, it has choices between offering a bit of CDR for summoners, items and spells or you can go for some sustaining, and also some free gold basically.|
|Magical Footwear is nice as it lets you sink gold into other items rather than boots. It takes 12 minutes to arrive though if you don't get any kp during early game so it can be quite harsh to take if you have a rough time in lane.|
|Biscuit Delivery is also a viable option to take on Jax, combined with Time Warp Tonic. It helps you in harder matchups and lanes where you need to sustain more, since Jax doesn't have the best early game and it's pretty easily exploitable especially the higher you go on the ladder. After the nerf though I would only take this into lanes I truly need the extra sustain early.|
|Time Warp Tonic is nice for lane phase, your early trading benefit from the movespeed boost while active and also the instant heal for half of the potions healing can catch your opponent off guard. Other choice is Cosmic Insight This helps gives you quite low cooldowns if you get Spear of Shojin with Trinity Force since that makes you have 40% CDR + 5% from Cosmic Insight.|
As for the stats you choose the attack speed one is really helpful, but the other 2 you should decide based on the opposing team, I usually end up grabbing the adaptive force + armor but vs AP lanes taking MR will be beneficial.
|If you want to go for more defensive runes then take the Resolve tree.|
|For the first rune I would probably Bone Plating. It helps you in lane with your trades. After it procs it reduces the damage your opponents next 3 attacks/abilities deal to you by 25-50 depending on your level (works only for 1 enemy at a time).|
|Second rune choice is Demolish. It allows you to push towers down even faster, especially now that turret plating is added to the game this will help you take down those plates faster than ever.|
Here as well the stats you choose should be decided depending on opponents. The attack speed one is really helpful, but the other 2 are more depending on do you need resistances/extra HP. Adaptive Force also feels solid for going agro early
|Sorcery became a more appealing secondary tree again after Magical Footwear nerf. Sorcery offers tools to scale into late game and also some laning help with Nimbus Cloak/ Nullifying Orb.|
|You can take Nullifying Orb for heavy AP lanes like Swain, Kennen, Heimerdinger etc as it helps you a lot since it's like a mini Hexdrinker. Also Nimbus Cloak can be fun to try in some cases as it can score you that kill that is just out of reach.|
|Transcendence is nice for the CDR and damage after capping it out but though it sucks that it only becomes effective after level 10.|
Other choice for the primary rune tree is to take Inspiration and grab Kleptomancy. It used to be a really strong keystone for a while. Now in Pre-season 9 they changed it to grant 5 gold or something better on the next 2 basic attacks after a spell cast which makes the rune overall stronger. Jax can pretty easily proc it in lane with his Empower or Leap Strike. It helps those lanes where you need to scale faster while you won't have the chance to kill your opponent that often (vs tanks etc). After that you take Perfect Timing, Future's Market and lastly Cosmic Insight. To be honest I never run this setups as I almost exclusively run Conqueror apart from when I'm jungling.
Relentless Assault (Passive): Jax gains bonus attack speed for 2.5 seconds every time he lands a basic attack, stacking up to 8 times. This falls off one stack at a time. To utilize this passive in lane auto attack minions as much as you can before engaging the enemy so you have more attack speed to fight with.
Leap Strike (Q): Jax leaps to targeted enemy while dealing physical damage to the target. It can also be used to jump on wards, plants, Thresh lanterns etc. If you use your W before using Q the W's damage will be applied on top of your Q's damage.
Empower (W): Jax's next basic attack or Leap Strike within 10 seconds deals bonus magic damage. It is also an autoattack reset so after your auto attack has landed activate this for and immediate autoattack. They also added 50 more range on this ability in the patch 7.12 which is really nice since it makes this ability easier to land on a running opponent.
Counter Strike (E): When activated the first time Jax will block all incoming auto attacks for 2 seconds aswell as will take 25% reduced damage from all area of effect abilities. At the end of the duration or when reactivated Jax stuns nearby enemies for 1 second and deals physical damage to them, increased by 20% for each attack dodged, up to a 100% increase. This is the key to winning melee matchups at level 1. Just auto minions for your passive and then auto the enemy while near his minion wave so your E's damage increases.
Grandmaster's Might (R): It's passive enables Jax to deal bonus magic damage on every third basic attack within 2.5 seconds of each other. When activated Jax gains bonus armor and bonus magic resistance for 8 seconds. Once you hit level 6 in lane auto minions twice and then Q onto your enemy and autoattack and follow with immediate W for a good amount of burst.
|You want to be taking points on Grandmaster's Might whenever possible. Out of the basic skills you want to max Empower most of the time for maximum DPS. In some ranged matchups maxing Leap Strike might be the better choice, against champs like Gangplank, Kayle, Gnar and so on. Maxing Counter Strike isn't worth in my opinion, as you get much more out of maxing Empower and Leap Strike.|
Titanic Hydra, the god of wave clearing
This item is extremely efficient when looking at it's stats. It gives Jax HP which is always good especially early on, some damage and most importantly it improves Jax's wave clear immensively.
Trinity force, never skipperino
Maybe the most important item for Jax. It gives Jax everything he can want. It has nice boost on his attack speed, some damage, movement speed, but most importantly it gives him the Sheen proc that makes Jax deal so much damage in short bursts.
Hextech gunblade, the endless sustain
This item gives lots of healing and some nice burst to kill squishies aswell as let you live longer in fights since it heals you for 15% of all damage you deal.
Blade of the ruined king, % health damage is good
This item is a good option if the opposing team has multiple tanky champs, or if your lane opponent is hard to stick with and you need some sustain as well (for example Singed)
It also gives you some attack speed which is always a nice stat on Jax.
Spirit Visage, healing improver
This item works extremely well with Hextech Gunblade as it improves it's already good healing. It was kind of nerfed in the patch 9.10 but I still think it's relatively good. It is also good against AP poke lanes since the repice item Spectre's Cowl grants you more regeneration after you have been damaged by enemy champion. It also gives nice amount of MR.
Spear of Shojin
It can be a fun and effective item, but with it you'll run oom fast. Think of this as a proper bruiser version of old Essence Reaver. It gives HP now which is good, but no mana/mana refund which really hurts you when you spam abilities and run oom shortly afterwards. Gives you a big powerspike but either you'll need a mana source Frozen Heart, or be ready to back constantly.
Randuin's Omen, death to ADC's
The build path got updated again and now it's again a sensible way to build it. I usually pick up Warden's Mail first and then build it onwards from there. Helps extremely well in auto-attack oriented matchups and later on it's slowing effect is nice in teamfights and it also slows enemies attack speed when they hit you so it lessens the enemy DPS.
Good for autoattack reliant matchups and also vs fed ADC's etc. Most of the time I go these boots unless the enemy comp has heavy CC which can be an issue. Late game it isn't as noticeable but it's still quite good.
Mercury's treads, the option for CC
Pretty self-explanatory, get this if the enemy laner or the whole enemy comp has a lot of CC as it can shut you down pretty well.
Guardian Angel, Aatrox passive for everyone
The item got a slight change, now builds out of a B. F. Sword and a Cloth Armor, it can be somewhat awkward to build as Jax doesn't need the huge AD you get from B. F. Sword but it's a efficient buy if you are getting focused a lot or you are the frontline of your team. If you have extra gold in late game and this items passive is down sell it and switch it for something else as the pure stats aren't worthwhile the wait.
Gargoyle Stoneplate, time to jump in to the fight
I don't build this item too often, but when I do damn does it feel good to jump in to the fight and just tanking damage for a long time. Stone Skin passive gives you +40 armor and mr if there are 3 or more opponents near you, so you will just have a lot of extra resistance then, then when you activate it you get extra hp also. You will lose 60% of your damage for 4 seconds but thats a worthy trade off imo, as if you build this item and you go in to a big fight you aren't looking to oneshot anyone at that time, rather soak up damage and after withering the opponents then killing them. Very good buy if your team lacks frontline or you just need to survive longer in fights.
Thornmail, the way to cripple an AD comp
This item seems to be really good in some cases now. If the opposing team has lot's of healing champions or just a fed AD champ with lifesteal this is the perfect item.
Thornmail applies Grievous wounds for 3 seconds which helps killing those pesky healing champs much easier. Also it has the cold steel passive which is nice.
Death's dance, bleed it out
This item got changed in 8.24 and it seems really good for Jax. Now it heals for 15% of ALL damage dealt, and as we know Jax knows how to deal damage. The DoT bleed passive is also nice which allows you to have more time in fights healing up, essentially it acts like a damage reduction.
Sterak's Gage, Tenacity and shields
I really like this item on Jax. It gives you some protection against burst, but also still gives you a bit more damage. So for the cost you get some AD, HP shield and +30% tenacity, which is a good stat on Jax. Only thing you need to keep in mind is that the shield doesn't pop every time, so this item is good if you are getting bursted a lot in fights and you need to also negate some CC when chasing down your opponents. This item isn't a must buy every game but it got a lot better than before.
His passive gives him more attack speed and he can take turrets down pretty fast after he get's Sheen. You just auto-attack and right as the attack has landed you use Empower for the auto attack reset and at the same time you get a Sheen proc. Also having Titanic Hydra helps splitpushing as your waveclear improves and it also gives you an autoattack reset.
Jax is also a strong splitpusher since he can duel pretty much anyone in the later points of the game and if you are ahead splitpushing is a great way of giving the enemy team pressure around the map.
Also thanks to his mobility with Leap Strike, Jax can escape sticky situations with his ward hop mechanic which makes him somewhat slippery as he can jump over walls.
When to splitpush?
When splitpushing you are essentially leaving your team 4v5, so your team needs to be aware of what you are doing. The idea of splitpushing is to either attract attention to you, so the opponents send 1-2 or more champions to deal with you which leaves your team free to take objectives with the overpower they have. The other case is that the enemy leave you unnoticed and try to take down your team, in which case your team needs to be aware of the risk and back off before it's too late. When this happens you push the lane you are splitting as hard as you can as you can get surprisingly fast multiple towers down from a lane.
When splitpushing vision is a really important thing. Try to have vision around the area you are pushing so you know when to back off if the opponents try to gank you from the fog of war. Also keep an eye on the minimap to see how many of your opponents are visible, and where they are. Think of who you can solokill and who you can't, who you can possibly 1v2 etc.
If you have Teleport while splitpushing you can also consider Teleporting into teamfights. If your team can hold on the fight while your TP is channeling you can win the teamfight with the element of surprise if the opponents first thought it will be a 5v4 fight for them. Before you tp consider which option gives your team the most advantage. If the fight is already lost pretty hard, push as much as you can and back, remember to keep vision on objectives like Baron Nashor and Dragon depending on the lane you are pushing since if the opponents kill your team they are likely to do one of these objectives if possible.
When you reach 6 a common thing to do is auto minions twice, then Leap Strike on to your opponent, auto them and immediatly follow with Empower. This combo will do good amount of damage as your Grandmaster's Might 3rd proc + Empower do quite a lot of damage in a short burst.
You can also cancel your autoattack animation with your Counter Strike. When you have activated Counter Strike and you have autoattacked, right as the damage from your autoattack lands re-activate Counter Strike and this will cancel the rest of your autoattack. This is very useful if you want to do a fast combo with your W and Titanic Hydra for example.
You should also note you can use your Leap Strike on things like Jarvan IV flag, Thresh lantern and so on.
Jax is extremely good champion at taking advantage of an lead and carrying your team to victory! He can be difficult to play against comps with lot's of heavy CC but even that can't stop the Grandmaster in some cases.
Any feedback on this guide is highly appriciated, I will be updating this constantly whenever there is something to update or new ways of playing Jax are discovered
Have a great time splitpushing and smashing enemies as Jax!
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Thank you to @Jovy for the awesome banners made for this guide!
Also some of the code used in the making of this guide is from http://www.mobafire.com/league-of-legends/build/making-a-guide-101506#chapter11 @jhoijhoi