I'm Asuryann, an Diamond EUW OTP Illaoi. I do a lot of theorycrafting on Illaoi, and i chose which items I use based on calculations. Illaoi is really not the strongest top laner, low mobility, no cc, and many counters. BUT it's enjoyable to play and surprising when your opponents don't know this champion's damage. Let me show you my vision of this sweet champion.

There is a fixed distance allowed between tentacles, and a bad positioning of your tentacles can put you in danger, then keep an eyes on the cooldown of your passive. You can time your tentacles spawn to outplay your opponent !

Can be used for farming, poking, spacing at a safe distance. This skill passively amplifies damage done by tentacles, I always Max my Tentacle Smash, because it is very important to kill the spirit made by your Test of Spirit.

Can be used to cancel your auto attack animation. Can be used to jump over walls, useful to gaps close or escape, with a ward on the Gromp for example.

The most important ability , failed it can kill you ! Use your Harsh Lesson to close the gap before using your Test of Spirit is strong. Tentacle Smash before Test of Spirit to killing the minions and surprise your opponent. The spell reveals the tethered target. Tentacle autonomously attacks the closest Vessel or Spirit, once every 4,5/4/3,5 seconds, based on level (respectively 1/7/13) Vessel spawns a Tentacle near themselves. Tentacles can spawn 300 units closer to each other than those spawned by your passive.

You can orient where your tentacles spawn. You can Leap of Faith and Flash during the animation. Use your ult when you going to be controlled. When you ult, the cooldown of your Harsh Lesson is halved, it can be useful to take a tower for example.

Of course, very useful to Leap of Faith Flash, reposition yourself in fight for a better position inside your tentacles. Flash Harsh Lesson with Sheen can make a surprise kill, a lot of people try to Flash and die miserably.

Strong Spell to win a lane, help to land your tentacle hit, to land your E, and usefull when your mate feed as well. Currently my always pick.

If you die, can fix your death, you can come back and don't lose a whole wave. Sadly because you have a TP with the Top quest, I think it's sub-optimal.

Against burst Champion. I personally don't recommend this one.

A rune when you want to play a lot early on. Very nice for trade, with your Sundered Sky/ Sheen too.

The only usable rune on this spot, good one because Illaoi can push fast.

Against all-in champion, you can buy a lot of time to survive, heal, hit your Test of Spirit and kill.

To Stay longer in the lane, Second Wind against ranged and champion who can easily proc Bone Plating.

Better than Revitalize (because of your passive Prophet of an Elder God) the more you advance in the game the more the skirmish is going to be short.

Like this table show you : Calculate with Black Cleaver and 1 Sterak's Gage, this table show how many Tentacle Hit you need to make Revitalize profitable.

Illaoi need mana in lane and this one scale fast, in competition with Presence of Mind.

This rune is why we use the sorcery tree, help to damage in lane with small trade, work well with Grasp of the Undying and Manaflow Band.

Illaoi Can stack it easily when she ults, and the extra damage that rune gives is really good. Sadly the rune is hard to stack early.

To wave clear Illaoi use her abilities a lot, a mana helping rune is essential.

The only choice on this line, Legend: Bloodline don't work very well on the champ.

You bait a lot with this champion and this rune helps us for that, very nice.

You can split push with Illaoi and the rune helps for that. Platings can give you a good amount of gold this season.

Survival is good, work well with Conqueror as well.

Boots

Versus multiple AD THREATS, really great for the champ because you need time to make your damage and sustain.

The boots I buy the most, Tenacity is Great, generally buy Sterak's Gage before buying the boots.

Playable boots, we need to buy them early to quickly gain omnivamp, generally after your first item. I buy this item vs heavy melee/bruiser comp.

Playable against champ who has a lot of slow, Nasus, Ashe. I prefer Mercury in a lot of cases.

Core Items

Really good early game, help to bully as well. Can be combine with Iceborn Gauntlet on third item.

Historically The Item for Illaoi, can be buy in second after Sundered Sky versus tank, or when you don't want Sterak's Gage

Only on second Item, for the resistance with the shield, the buff of tenicity in the Patch 14.1 is extremly good. I probably don't buy it vs Pyke or Renekton.

The next table shows the gold effiency of this item :

Cheaper than before, very good item, the slow is very nice for making your tentacles hit !

Situational Items

Versus Heavy AD or Crit. The Slow can be useful too, vs Tryndamere for Example. Can replace your Iceborn Gauntlet!

A good mid to late game item for Illaoi, work fine with your kit and with Sterak's Gage.

Awesome passive on Illaoi, he makes your Sterak's Gage better too.

Goof magic resist item versus rang AP or burst. Can help to survive heavy CC comp as well

Against AD champion with heavy heal. Upgrade the Bramble Vest for your 4rd Item maybe ? I think it's a bad item.

Good item to build after the core Item when you need tankiness. With your Test of Spirit you can stack it up before the fight.

Another damage item, your 3rd Item in some cases, can't replace your first in my opinion.

Illaoi can definitely use this, but need to be pick third or second, after that this item is less valuable.

Honorable Mention

Now unplayable against Mordekaiser... This is the end for this object

I think you don't want that, just Keep your Executioner's Calling, and when you ally have enaught anti-heal, sell it.

Good Item versus attack speed champion. Don't buy it against Master Yi, his ultimate ignores slows and attack speed slows.

I prefer the other magic resist items, but can replace the Sterak's Gage. I like combo it with the Death's Dance, the 2 items scale with bonus AD.

For decisive fight in late Item.

To know what we need, HP or Armor/Magic resist I make this Graphic:


The lines represent the point at which you will have the highest effective health against that damage type, with the base Armor/magic resist you have at each level.

If you want to learn more about this concept, go look the Fandom Wiki in the section Armor vs. Health

https://leagueoflegends.fandom.com/wiki/Armor

Matchups Difficulty

Matchups Runes

I don't think it's necessary to change runes based on the matchup. Generally, sticking to the same runes allows for greater consistency.

Specific Matchups: First Back Item

Depending on how is your lane going, in a lot of case I prefer finish my first item as fast as possible.

The placement of your tentacles is crucial, it determines where you can fight.
Poor tentacle placement can be disastrous, if a tentacle is in a wrong spot, this shifts the next tentacle out of reach to protect you.

Starting Position for Red Side

The first tentacle you place before your tower help you to place the others, especially when you come back from the red by your lane.


It's difficult to have a good tentacle placement safely when you come back by the river.

Starting Position for Blue Side

The first tentacle you place before your tower help you to place the others, in blue side you always come to the lane by this way.



Advice about your postioning :

If you want to protect a tentacle stay close to this one.
Don't take minion aggro too close of your tentacle in the early game, the minion protect your opponent of your Test of Spirit.
If you want to protect you stay between your tentacle, 2 is the must have.

Level 1

Use your Tentacle Smash to take the first 3 minions, and try to damage your opponent at the same time.

Level 2

Your level 2 is weak, just take the minions without trading too much.

Level 3

Now you can trade in the majority of matchup, but don't miss your Test of Spirit !

It's difficult to come for the first scuttle, your tentacles are not in the river to help you.

Level 6

You are finally more powerful than a Siege minion !
You can push your lane as long as your Leap of Faith is up. If you can bait a double kill on the jungler you probably win your lane instantly.

Throw your Test of Spirit at your enemy when they try to last-hit, if you miss it run away.
Pushing the lane is very nice, you want to be a lightning rod for the enemy jungler.

From the base you have the choice, Split push or group to fight around an objective.

How you determine that ?

Match up based

If the enemy top laner is strong in team fights you want to split push, to force him to stop you, like that he doesn't take a teamfight against your team.
If the enemy top laner is a strong split pusher you want to contest the push, go fight with your mate and come back to stopping him.

Put a pressure before Baron or Dragon is necessary, if you Teleport is up you can force your opponent to make a choice :
Lose a tower or lose the Dragon/Baron, and if they react in the wrong way, or slowly, you can take both.

Before Split

Ask yourself why am i splitting, what is the goal ? If your answer makes sense, you will improve.
Again, your pressure is a necessity, you need to learn how to use it.
Split pushing requires awareness to your enemy's movement on the map, you can distract them to secure objectives.

Teleport Teleport before the fight starts, and remember you need your tentacles.

When teamfighting with Illaoi the first thing you want is a good position, inside your tentacles ! where you can survive and easily proc your Test of Spirit.
Each Test of Spirit you hit puts a lot of damage and pressure on the enemy comp, they need to avoid the hit and clear your tentacule for a few seconds.
For those few seconds, you and your teammates can take better positions, or force the fight to your advantage.

Attract your opponent allow your mate to DPS properly, the main goal is winning the fight, if you die for it, it's fine.

It's difficult to explain how to fight, you need to know your damage and how much damage you can take.
Experience is the key.

Most of your good trades starts with your E, and you need to focus the spirit, if your opponent becomes a vessel the trade is winning in the majority of cases.

The Basic Trade Pattern :
-> AA -> -> -> AA

You always want to place your Q after an Auto or your W to maximize your damage.
In some cases, you must not use your AA before your W to kill the spirit before your opponent gets out of your reach.

Trade Pattern with your Ult :
-> -> -> ->AA-> ->AA->

You should damage the spirit before your ult, in order to bait your opponent, when he is close enough ult him with his spirit.
The low HP spirit will rapidply die and slow your opponent who become a vessel, the tentacles will hit him automatically.

Thank you for watching this guide to the end.

And this is how I make my table :

All HP numbers are the damage you take with your resistances, and without armor/magic penetration.

Life with Overgrowth full stack
VS AD and VS AP calculates the total damage you can take with your current HP and Resistance
HPT = Healing of your tentacle / CD of your W (at 30%hp)
Number of seconds to make Revitalize profitable = (VS AD of Overgrowth - VS AD of Revitalize) / ( Life*(%HPS Revitalize - %HPS Overgrowth) / 100 )

The theoretical equilibrium is calculated with available information on the fandom.

The base equilibrium line for armor is a function:
health = 7.5 × (armor + 100)
for magic resistance:
health = 6.75 × (magic resistance + 100)