Every jungler who wants ever to be good needs to know how to play Lee Sin

MYTHICS:

Default mythic for Lee Sin. Gives a lot of damage and sustain while making you tanky, standard.

Similar alternative to goredrinker for more utility (slowing enemy) on the cost of survavibility.

Very strong against a lot of squishy members, I've seen it a lot in lower mmr by Lee Sins since you are able to snowball like crazy.

OTHERS:

Very strong item atm. Highly cost efficient. Build it whenever you have good gold for it, and if your team needs healing reduction buy it, the stats are worth a TON of gold and you will save the trouble of some of your teammates having to buy heal-reduct.

Very strong item in general for bruisers. Will be worth going for in most of the games, especially if enemy have ad assassins or a lot of physical dmg in general.

Strong if enemy has a ton of magic damage, especially mages that need to burst you down quick such as Diana. However, will leave you squishy in terms of HP, so you might only wanna go for Hexdrinker, build some HP and then finish this item later. Cannot combine with Sterak's Gage! (same passive)

Histrorically has always been a great item choice for Lee Sin and likely always will be. Is great esp. against armor builders, makes you way more tanky and gives Ability Haste. Imo another item that is strongly underrated atm.

Used to be great 3rd item, and is still possible if you want to jump in all the time and if you want to keep building in the tank-ish path. These days is rather replaced by Maw, Randuin or GA Cannot combine with Maw! (same passive name)

Very strong item if enemy has a lot of physical damage and critical dmg dealers (Yasuo/Yone in enemy = go this).

Broken item against a lot of magic damage and CC. This turns a bruiser into nearly unkillable tank if enemy has many magic dealers and the extra MS will always come in handy.

Veeeery strong item for champions like Lee Sin, Vi, Jarvan especially in late-mid or late game. Very underrated item imo but, don't forget to use it! Stopwatch part of this item makes it so that you can go nuts in one fight with your kick and press SW to buy insane amount of space.

Works great if you build a lot of damage (such as Eclipse mythic path) => let's you assassinate one target, ideal if it's an immobile carry, then buys time for your team to clean up the fight while you respawn.

Good item choice if you were building full tank the entire game but now you want some damage.

If you want some extra tankiness with armor and chase down enemy carry, or just need to be able to always reliably engage, solid option to go for but there are usually better choices.

note: insec play means jumping on a ward / flashing behind your opponent and kicking him towards your team. You can also do that with R->Flash, in that order, if you are quick enough. Note that Lee Sin R can't be QSSed anymore therefore there is no outplay to it beside flash/stopwatch.

With Lee Sin, as with every dominant jungler these days, you wanna focus on ganking all your winning laners in early game, possibly diving and taking herald + dragons (both single targets - easy to kill for lee sin).

Very brief Lee Sin ganking TLDR:

Lee Sin brings strong skirmishes and 2v2/3v3 situations, against most of the junglers.. Until level 6 you are looking to gank laners who are behind half of the lane, or diving opponent with low hp, keep in mind your second Q is execute damage and can be key in those situations.. This dramatically changes after lvl 6, you suddenly can come from behind the tower / from alcove with insec plays, especially around mid lane, where you can ward jump from raptor's camp wall and kick enemy laner inside of yours, in sutuation like that you always look for W(over-wall)->R->Q->Q->AAs etc.
Lee's kit provides with an amazing counter gank power. If you manage to know about enemy jungler's incomming gank, counter ganking as Lee Sin will work in most of the situations.

If you start solo you can start with W lvl 1 to not get as much dmg from the camp, the kill speed is howerver sligthly slower, most jgls still prefer Q + smite first camp.

You can always look for a nice Insec play, or rather flank in many situation. With flanking enemy comes one big issue as Lee Sin, you don't wanna have red trinket therefore you don't usually know if you are no wards or not. If you are able to move through jungle and look at nearby enemy at the same time, you can judge if you are being seen or not based on their movement. Overall, you always want to look for flanks from areas which your support has cleared (de-warded) before.
If some of your carries is ahead of the game, you can utilize your Kick simply as peel/(protection tool) for him, this should especially be done in late game. Also keep in mind that W is not a weak shield, and can very often save someone so watch out.
Situational play if one enemy carry is super fed is that you can jump towards him in fight, kick him away (or to your team) and use Q to get back into the fight.

In late there is usually a hyper carry that deals 10x as much damage as you, unless you are 15/0 and it's not late game for others yet. In such situations, unless you find a good flank for kicking someone to your team (do not touch that malphite!), you usually use your kick to peel your carries.. If you have additional back-line access in your team, such as mentioned malphite or camille / talon, you can also jump into back line as lee sin's execute damgage is pretty solid even in late game and that might be just what your carry needs to destroy enemy backline, but keep in mind that if you go deep your carries might die to opponent's frontline, you must always value where you are the most useful for your team, and whether should you play for them or selfishly.

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