First of all I am of course not the real River Shen, but he is my rolemodel and I really want to show the path and style of River Shen to every league player.
What makes River Shen to River Shen?
River Shen is a roaming support who lives in the river.
A River Shen is constantly ganking other lanes and has to take Ignite and Exhaust. He will try to take every Rift Scuttler and can only say "River Shen". A River Shen will try to snowball midlane and toplane as hard as possible.
The classic River Shen buys Boots or Doran's Blade first. But I am not the real River Shen so I would go
Steel Shoulderguards first because you can use it very well after ganking and it still has the spirit of the supportive River Shen. The real River Shen also couldn't buy this item because it is pretty new.

Credit

The first documented footage of a River Shen is this video, it was only a recreation of a real game. It was released on the 27.01.2015 and it inspired many players to follow the holy path of River Shen. The Account of the River Shen is AVLeeuwenhoek (EUW)(OP.GG/ U.GG/ LoLProfile/ Mobalytics/ Leaguespy).
He is just a recreation of the real River Shen but he also played some games like a River Shen this season. His name is probably from the Dutch microscopist Antonie van Leeuwenhoek who first observed bacteria and protozoa.
On the 25.01.2016 Riot Games confirmed River Shen as an actual role besides Toplane and Jungle (YouTube (0:47))

On the 20.06.2018 the Youtuber Pianta released another documentary about the River Shen with more deatiled Information. Just a month later he made a heartbreaking song (1) (10.07.2018) with OzzaWorld about the Legend of River Shen. One more video (31.03.2019) and two more song (2) (07.08.2019), song (3)
(30.08.2020) were following.

I have a theory about River Shen.
I think it is no coincidence that the Item Sheen is very similiar to Shen. The Blade Sheen is blue like Shen's Spirit Blade. Since the Kinkou Order has a strong bound to the Spirit Realm the Kinkou Order could be also connected to the River Spirits (from TFT). My theory is that there is a River Spirit in the blade Sheen. That is maybe also the reason why River Shen is so deeply bounded to the river. This theory would also say that another name for the Spirit Blade would be River Sheen.

Another theory is that River Shen is actually not killing the Rift Scuttler he is freeing the spirit of the Scuttler so that it can go into the Spirit Realm. This is not comparable to Ivern passive Friend of the Forest, because Ivern is not leading the spirit of the Rift Scuttler to the Spirit Realm. River Shen gets rewarded for the freedom of the Scuttle Crab with Gold, XP and Health. The spirit of the Rift Scuttler could be the River Spirit from TFT. Because it is also connected with the River.

PROS Great vision in the river Good Map control High snowball potential for the Midlane, Toplane and Jungler Pressure on the enemy Midlane, Toplane and Jungler

CONS 1v2 on the Botlane XP disadvantage for River Shen Easy trap potential in the river Your Teammates will probably flame you. If you are not the real River Shen you will probably lose the game.

The Team Composition around River Shen is very important.
The perfect situation is to play with 4 of your friends because then you can't make any uninformed player
angry ( Undying Rage) or toxic ( Insanity Potion).
You can also go a bit further and play as a whole River Team but more to that later.


The perfect Botlane:
There are two options for a perfect bot lane:
First a Adc with high range auto attacks or abilities and good Escape-Tools like Caitlyn, Ezreal, Tristana and Kai'Sa.
Or a other Champion that can play a 1v2 ok without getting killed or losing too much cs and xp. They should have sustain, range auto attacks or high range abilities and good Escape-Tools like Dr. Mundo, Maokai, Ornn, Gnar, Jayce, Illaoi and Yorick.
I am not sure about some champions so please leave some helpful comments! <3


The perfect Midlane:
A River Shen and the jungle champion will gank the Midlane a lot so it would be good to have a champion with a high snowball potential like Kayle, Syndra, Veigar, Diana, Kassadin, Katarina, Talon, Zed and Yasuo.


The perfect jungle champion:
The jungle champion should be also a good carry for your team like Master Yi, Jax, Karthus, Kindred, Twitch, Evelynn, Tryndamere, Rengar, Kayn and Kha'Zix. The jungle champion can farm much more because River Shen is already ganking a lot, he can also invade a lot with River Shen on his side and he can also secure Drakes and Heralds easier with River Shen.


The perfect Toplane:
The champion on the Toplane is not so important it can be a carry champions like Kayle, Teemo, Vayne, Fiora, Quinn and Nasus. But the enemy Botlane can also rotate to the Toplane because your Botlane is something like Dr. Mundo or Maokai.
The Toplane can be also a tank when the other allys already carry champions are.

The runes of River Shen are very variable, you can choose your play style. Except of Waterwalking every River Shen has to take this rune, because it fits just perfect.
The runes should synergies with the items.
Domination and Precision runes should be combined with bruiser items.
Resolve runes should be combined with tank or support items.
Support items are also good with Inspiration and Sorcery Runes.

RESOLVE

Guardian is good because you can combine it with Stand United and you can proc Shield Bash with it.

Aftershock gives good tankiness and damage but it can only be activated by Shadow Dash so it is not that reliable.

Shen has many shields so it is the perfect rune.

This Rune is good for early trading and invades.

Against a lot of damage Revitalize makes shields and heals stronger.

Against a lot of crowd control Unflinching because it gives tenacity.

DOMINATION

Hail of Blades gives great early game damage.

More movement speed is good for ganking and roaming.

Bonus true damage when Shadow Dash hits.

Bonus damage for ward destroying.

Bonus damage for good ward placing.

Bonus damage for takedowns.

Gives bonus movement Speed for takedowns. Which is good for roaming.

Reduces the cooldown of Stand United for takedowns. Stand United has a really high cooldown and is a very strong ultimate.

SORCERY

Gives movement speed for ganking and escaping.

Against a lot of magic damage. (Can also activate Shield Bash)

Good movement speed boost for ganks after using Summoner Spells.

Cooldown reduction for Stand United.

Movement Speed and it also looks a bit like Shadow Dash.

Synergy with health items.

River Shen is not River Shen without that Rune. Waterwalking was just designed for him.

PRECISION

Good for 1v1 in the river.

]

Good synergy with a lot of attack speed items.

Triumph gives 20 bonus gold for takedowns and some health.

Bonus attack speed is always good.

Good against a lot of crowd control.

Coup de Grace helps ganking low health enemies.

INSPIRATION

Good slow for ganking mobile enemies.

River Shen can use a lot of Keystones so why not try all of them at once?

Magical Footwear are a good way to save 300 gold for buying boots.

Saving gold is always good when playing River Shen.

45% cooldown reduction is very good for Stand United and Shadow Dash.

RUNE SHARDS

X

Attackspeed

Cooldown Reduction

Damage

Armor

Magic Resistance

Armor

Magic Resistance

Health

SUMMONER SPELLS - EXHAUST: Exhaust is good because it gives you more kill potential when you gank. You can also avoid getting killed by lane bullys like Darius or Mordekaiser. Exhaust the enemy first to hit your E and Q easier. IGNITE: Ignite is also good for early kill potential and good against Champions with a lot of healing.

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FIRST ITEMS

Boots of Speed

Doran's Blade

Steel Shoulderguards

The first items of River Shen are very controversial in the first video of River Shen AVLeeuwenhoek was building Doran's Blade, it gives good early game stats. But in Season 10 AVLeeuwenhoek is building Boots, those are good for mobility. Pianta is also building Boots in his Videos. I think Steel Shoulderguards is a very good item for River Shen because it gives him more gold and is supportive for the ally team.

Sheen Sheen is the after my theory the blade from River Shen without the River Spirit in it. That's why he needs it in combat to protect his allies. It also has a pretty good passive and is a part of Divine Sunderer and Trinity Force which are a good item on River Shen.

BOOTS

Boots of Mobility These are the best boots for River Shen because they give a lot of movement speed for roaming.

Ionian Boots of Lucidity Cooldown Reduction is necessary for River Shen, this boots can fill a lack of Haste when River Shen builds items like Titanic Hydra, Thornmail or Randuin's Omen

Plated Steelcaps This boots are only good when the enemy team has a lot of attack damage.

Mercury's Treads This boots are only good when the enemy team has a lot of magic damage or crowd control.

Boots of Swiftness This boots are only good when the enemy team has a lot of slowing effects.

BRUISER/ TANK BUILD

Titanic Hydra River Shen is not farming very much, but the extra damage and the scaling with health is still very good.

Sterak's Gage This Items gives River Shen healing and a shield that scales with Health, which is good because Shen is already scaling a lot with Health.

Spirit Visage Spirit Visage gives good stats and it is also increasing the healing of some of the item passives and Health regeneration.

Death's Dance Zeke's Convergence also has good resistances and Cdr. The Passive can be activated very easily with Stand United. It also has useless 350 Mana.

Adaptive Helm Zeke's Convergence also has good resistances and Cdr. The Passive can be activated very easily with Stand United. It also has useless 350 Mana.

FULL TANK BUILD

Warmog's Armor Shen has a lot of health scaling on his abilities. This items grants also some Cooldown Reduction.

Spirit Visage Grants health, Magic Resistence and Cooldown Reduction. The passive works well with the Base Health Regeneration from Warmog's Armor, Titanic Hydra and Adaptive Helm

Thornmail Zeke's Convergence also has good resistances and Cdr. The Passive can be activated very easily with Stand United. It also has useless 350 Mana.

Adaptive Helm Zeke's Convergence also has good resistances and Cdr. The Passive can be activated very easily with Stand United. It also has useless 350 Mana.

Randuin's Omen Zeke's Convergence also has good resistances and Cdr. The Passive can be activated very easily with Stand United. It also has useless 350 Mana.

Randuin's Omen Zeke's Convergence also has good resistances and Cdr. The Passive can be activated very easily with Stand United. It also has useless 350 Mana.

Randuin's Omen Zeke's Convergence also has good resistances and Cdr. The Passive can be activated very easily with Stand United. It also has useless 350 Mana.

SUPPORT/ TANK BUILD

Knight's Vow Cheap item with Cooldown Reduction and armor for River Shen and an ally. Cooldown Reduction is always good and the armor can be very good on a carry in your team.

Shurelya's Reverie Shurelya's gives Cooldown Reduction, Health and Base Health Regeneration. The +10% Shield Power are very good for River Shen because Shen has a lot of shields. The activ bonus movement speed is good for ganks and team fights. The +100% Base Mana Regeneration is sadly useless.

Righteous Glory Great engage and gank item with good Cooldown Reduction. Sadly it also has 100% Base Mana Regeneration and 300 Mana.

Zeke's Convergence Zeke's Convergence also has good resistances and Cdr. The Passive can be activated very easily with Stand United. It also has useless 350 Mana.

River Shen always max his Shadow Dash because it looks like the dash of the rift scuttler and because of the lower cooldown. Shadow Dash is also good as a escape tool because River Shen has no Flash.

Twilight Assault should be the second max because it gives River Shen a good amount of damage.

River Shen strongest time is the early game. At the beginning of the game only the River Shen gives the jungler a leash. The botlane can go early to lane to get some sort advantage in the 1v2. After the leash the River Shen goes immediately to the Toplane or Midlane and tries to gank his opponent, so the ally can get First Blood. After this Gank a River Shen ganks the other lane. After the first or the second Gank the Rift Scuttler should spawn, which is a important XP and Gold source for River Shen. The Rift Scuttler will spawn first at 3:15 at the top and bottom half of the River. When River Shen kills the Rift Scuttler it leaves a shrine behind that gives the allied team movement speed and vision in that area. This shrine will last for 90 seconds and after 55 seconds a new crab spawns (2:25 minutes in total). If the River Shen still has enough health he ganks Botlane with the Jungler. A River Shen helps after ganking to controll the wave with or without Steel Shoulderguards. After this Gank a River Shen will recall to get some items from the shop. After that he will just keep ganking and taking Rift Scuttler.

In the Mid and Late Game River Shen is of course still taking Rift Scuttler,
his home is the river and he can only say River Shen. But without these things River Shen will play like a normal Shen.

Now have fun playing but never forget the spirit of the River Shen:
Be protective, all-map-caring and always come back to your river!

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