Welcome to my Lee Sin guide. I'll be offering as information as possible on this champion, and will try to help you become better not only with this champion, but as a jungler in general.

Lee Sin is one of the best (if not THE best) champions in the game. He has a very strong early game, which means he can pressure lanes or the enemy jungler and give his team an easy lead early on. By the mid game, he helps establish vision control for his team with Sightstone, and then becomes a tank/peeler late game. He does have a lot of utility and takes a while to master, but the time spent is well worth it.


***Disclaimer*** Still under construction.

Pros
Works with any team comp
Great ganks
High mobility
High skill cap
Fun to play

Cons
Hard to play
Scales poorly

Greater Mark of Attack Damage: These allow you to do more damage, obviously. Greater Mark of Armor Penetration can be used as well, but I feel like it's a weaker option. Attack speed isn't necessary, because of Flurry.

Greater Seal of Armor: These will offer you more sustain in the jungle and in fights.

Greater Glyph of Magic Resist: These also offer more sustain in fights.
Greater Glyph of Cooldown Reduction: If the other team has little/no magic damage, you can take these in place of magic resist.

Greater Quintessence of Attack Damage: Same reason as Greater Mark of Attack Damage.

21/9/0 are standard AD jungler masteries. Sorcery is a better pick than Fury , because Lee Sin's passive, Flurry already increases his attack speed. You can take the point out of Expose Weakness for a point in something else.

Tank or damage?

Generally, you should build tanky, because the jungler is expected to do so in the current meta. However, if your support is a tank, you can build damage instead. If you build damage Lee Sin, don't buy Sightstone and keep in mind that you are squishy.

Always take Sonic Wave first, then Safeguard, followed by Tempest. Sonic Wave should always be maxed first, and you usually want to max Safeguard before Tempest, because you will have more sustain this way. And of course, max Dragon's Rage as soon as possible.

For buffs, keep your Smite until its health is low enough for Smite to kill it.

A good way to approach a camp is to Sonic Wave on a monster, then Safeguard yourself, close the gap with Resonating Strike, activate Iron Will, Tempest, do two auto attacks, and finally cast Cripple.

An excellent way to steal a buff while the enemy jungler or team is working on it is to Sonic Wave, Resonating Strike in, then Smite when the buff has low health. This is especially useful if you steal dragon or baron.

Lee Sin can ward jump (use Safeguard on a ward and he will jump to it) to initiate ganks, escape, or just get around faster, so Sightstone is a very powerful item for him.

Cast Sonic Wave over a wall to hit creeps and activate Resonating Strike to go through the wall. This will allow you to farm faster, initiate ganks, or escape the enemy.

Flash and Dragon's Rage is a good combo. Simply flash behind an enemy, and kick them into your team. Carries or lone enemies should be your target when doing this. Additionally, you can do the same thing with a ward jump if you are quick enough. If you can do this, you are always a threat.

Try to gank as often as possible early game, as Lee Sin has a very strong early game.

If you Smite with Iron Will, you will get even more health.

Use Dragon's Rage to keep enemies away from your carries, or to kick their fleeing squishy into your team.

Lee Sin is a strong champion early game and mid game, but he falls off late game, due to not having the best tank stats. He has a very high skill cap and several cool tricks, but takes time to master.

Thank you for reading my guide. I hope you learned something from it. I will continue to update regularly, so any criticism or comments are appreciated. Good luck out there on the rift, and remember to Lee Sin to your heart.