THIS GUIDE IS A WORK IN PROGRESS
There obviously incredibly viable champions in this mode such as Rammus and Heimerdinger, but since this game mode is new, I'm still experimenting.

As you may know, there are plenty of standard guides with builds that can fit most champions on Summoner's Rift ; however, you're going to want to think a bit differently on Dominion since you get your hands dirty right from the get-go. I choose Ghost because mobility is top priority in Dominion. Exhaust is my 2nd spell because it works well with harass and retreat.

By nature, this champion will be in the fray, chasing individual opponents, unprotected by their minions, and vulnerable to a Sonic Wave. Tanky is often the way to go with Lee Sin, but leaving a lane is far less punishable in Dominion. As long as you can escape with Safeguard / Iron Will and grab a health pack and a speed boost, you can find some minions to lifesteal to get back into the brawl or regain enough health to safely channel at a deserted capture point.

Never forget Lee Sin's passive! You have 2 fast hits before you need to use another spell. Be unpredictable. Sometimes it's not always best to initiate the same way every time. Don't be afraid to double tap your E if the kill is within reach, and don't feel required to target someone with W when you could simply Alt+W. Also remember that this build emphasizes more on dealing 1 on 1 damage versus thick team fights.

In Dominion you have a hefty start. I take the same runes as I do in Summoner's Rift with the exception of flat Magic Resist. Because you start at level 3 and progress faster, MR/lvl will be more desired. The armor penetration will help crush those who underestimate level 3 Sin. And of course flat armor helps more than just physical damagers--it helps with fighting in enemy minion mobs and at turrets the enemy already possesses. Movement speed obviously is incredibly valuable in this game mode.

In most circumstances I would go 21-0-9, but the buffs are too minuscule to consider increasing their duration by 15%, and you'll keep your level up to par if you stay alive. I could understand the utility tree for summoner spell CDR, but the game is just too fast paced to be awaiting an exhaust CD. Surprisingly, if you've checked out the end results of your games as Lee Sin, you'll see you do substantial magic damage, so I figure the 15% magic pen is worth it.

Even with just Boots, you are extremely agile even with your Sonic Wave / Resonating Strike and Safeguard / Iron Will at level 1. Since you're energy based, you can fly around the map even without mobility items. While Triforce and FoN may seem appealing due to Dominion's meta of mobility, you can keep on your feet, jump in or retreat without them if you play well.

Bilgewater Cutlass is amazing in Dominion. Rarely at all will you full on 5v5 team fight. It's comparable to a damage dealing exhaust.
Mercury's Treads are great for keeping the fight going, however I've seen some effectiveness in Boots of Swiftness and Mobility Boots.
Hextech Gunblade, to finish off your Bilgewater. Alternatively, if a team had a major magic or physical source I may work on some sort of defense
Hexdrinker deflects those annoying nukes who think that since you're not building tanky, you can be bursted down. Think again Mr. AP nuker! I find this item incredible for Dominion since you'll be making confrontations every minute! With a 45 second cooldown, it's comparable to the shield you get at the center of the map. And of course the damage bonus helps quite a bit too! Rather than having a flashy Banshee bubble above you (even though Banshee's disabled), you can have a deceptive magic shield.

By now you have 95 attack damage coming from your items. And although you may have found the 75 AP useless, you'll be surprised on how much you can recover by slamming down on a group of minions with your Tempest / Cripple. Pick up a vampiric scepter for a nice 32 life steal. And you'll have enough sustainability to maintain your points while getting the massive amount of passive gold to buy the bread and butter Dominion DPS items, Sanguine Blade, and chaser item Entropy.

Your final item, most likely a form of defense, if not previously picked up, is ultimately up to you to decide for circumstantial purposes. Remember that there's no Banshee's Veil--I tend to get a Thornmail given the bulky AD champs I've had to deal with so far. At 18, if and when you get there, you'll have 48.6(glyphs) + 25

I start with level 2 Sonic Wave / Resonating Strike to initiate and level 1 Tempest / Cripple to slow. Immediately after you cap your first point, you can ghost and initiate with a teammate or two and hit a slow for a kill or at least damage to the point where they'll want to retreat.

At level 4, get Safeguard / Iron Will as this will be, for the most part, your retreat. However, there are dozens of targets to choose from with this incredible skill, so use mind games to your advantage! If you're going for a point and know that a few people may be headed your direction, you can walk around the inside circle and jump back out to a teammate or minion to get back into the action.

From here on, your priority is R-Q-W-E. E is maxed last because the duration of the slow never increases, only the amount. Your core damage comes from Q and it has multi-functional use.

Playing Lee Sin the first time is no easy feat, but he is one of the most rewarding champions to learn since there are many variables in engagements.

Some things to remember when playing in Dominion as Lee Sin
- If you build more tanky and defensive, you're more apt for team fights--Dominion was made for the arrogant carries in Summoner's Rift who say "1v1 me!" So by backing your fights up with heavier damage and sustained lifesteal, you can keep those pesks off your territory.
- Never be too reluctant to retreat! If you feel you've lost the fight, you have 4 other territories that could need your attention! If you die, the few seconds you lose have a higher magnitude than the seconds you lose at Summoner's Rift.
- Like Tristana, LeBlanc, Kassadin, Ezreal and other "jumper" champions, Lee Sin can turn around a fight, given you land your Sonic Wave / Resonating Strike. Although this build is great for 1v1ing, don't get caught by the same ordeal that you can create.
- Capturing points is imperative! Don't spend your time chasing or lurking around enemy points when many opponents are missing, unless you're sure you can dash away safely.

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