Hi guys. I'm TopDiffed, a top laner who has been playing since S6 and I have climbed all the way to master tier in Solo Queue. I wanted to make some guides to show you tips and tricks for my favorite champions before getting into streaming. I hope my guides are helpful to let you hone your skills and give you some tips you have not seen elsewhere before. I have played a ton of Illaoi, and I think she is very strong and a good sleeper OP pick right now in the lane.

Pros:

Great counter pick into tanks
Very good 2v1 potential
Great powerspikes on items
Good side lane pressure

Cons:

Terrible blind pick, easily countered
No mobility
Unconventional playstyle top, unlike most other laners

Prophet of an Elder God (Passive)

INNATE: Periodically, Illaoi spawns a Tentacle on the nearest terrain perpendicular to her location, if no other Tentacles are already nearby it. Tentacles fully spawn after a 2 second delay and are Untargetable icon untargetable in the meantime.
Tentacles are commanded to attack by Illaoi's abilities.

Illaoi's passive is a core part of her kit. All of your abilities mostly revolve around your tentacles. A great tip I like to remind people of on her passive is that you always want to get to lane to set these up early on both sides of the lane. This will help you harass your enemy with your W when you have more tentacles set up. Try to defend these if you are able to in lane.

Tentacle Smash

PASSIVE: Tentacle damage is increased.

DAMAGE INCREASE:
10 / 15 / 20 / 25 / 30%
Tentacle Smash
ACTIVE: Illaoi slams down a Tentacle in the target direction.

This is your waveclear and main harass ability. Use this in lane to trade early, even when you don't have a soul rip. It has extremely high base damage and is a very strong Q ability.

Harsh Lesson

ACTIVE: Illaoi's next basic attack within 6 seconds gains Range icon 225 bonus range and causes her to Dash leap to the target's location if they're beyond her normal basic attack range.

The attack deals bonus physical damage, with a minimum threshold, and capped at 300 against non-champions, and commands all Tentacles in range to attack the target. The minimum bonus damage can also be applied against Turret icon turrets.

Our W immediately makes out tentacles slam down on the enemy. This is what makes our R ability so powerful. When the enemy is near a tentacle, make sure to trade onto them with W for extra damage. This ability synergizes amazingly with Iceborn Gauntlet as it procs the slow instantly.

Test of Spirit

ACTIVE: Illaoi launches a tendril in the target direction that stops at the first enemy hit, pulling their Spirit out in front of Illaoi over 0.75 seconds if they're a Champion icon champion. The target is Focused Resolve tethered to the Spirit for 7 seconds, True Sight icon revealing them in addition to granting Sight icon sight of the area around them while the tether remains.

The Spirit spawns with the target's Health icon current health, Armor icon armor and Magic resistance icon magic resist, and redirects a portion of the pre-mitigation damage received to the tethered champion.

DAMAGE TRANSMISSION:
25 / 30 / 35 / 40 / 45% (+ 8% per 100 AD)
When the Spirit is killed or the target leaves tether range, the tether is severed, marking the target as a Vessel for 10 seconds and Slow icon slowing them by 80% for 1.5 seconds once the tether returns back to them. Each Tentacle autonomously attacks the closest Vessel or Spirit, prioritizing the latter, once every 5.5 / 4.5 / 3.5 (based on level) seconds.

Vessel
Enemies made a Vessel also spawn a Tentacle near themselves every 5 / 4 / 3 (based on level) seconds. Tentacles can spawn 250 units closer to each other than when spawned by Illaoi.

Illaoi's BEST ability. This is such an overpowered basic ability. Once we land it, the opponent is almost always forced to run away and take extra damage. The best advice I have for anyone trying to get good with Illaoi is get into practice tool and WORK on hitting this. This skillshot can be difficult to land, and we need to avoid hitting minions with it as they block it. Illaoi's soul rip when landed makes her one of the most oppressive top laners in the entire game. If the enemy is low at all from our trades and Q, once we hit 6 and land an E. We can all in with our R and kill the clone and chase down the opponent for a kill most times. If they try to fight us in our E rip, we will win 9/10 times in an even game.

Leap of Faith

ACTIVE: Illaoi gains Unstoppable icon displacement immunity and leaps into the air for the cast time. She then slams her idol into the ground, dealing physical damage to nearby enemies. For each enemy champion hit, a Tentacle is summoned for 8 seconds (up to a maximum of 6 summons).

PHYSICAL DAMAGE:
150 / 250 / 350 (+ 50% bonus AD)
For the duration, Harsh Lesson's Harsh Lesson's Cooldown icon cooldown is halved, all Tentacles awakened by Illaoi are Untargetable icon untargetable, will not show their hitboxes, nor go dormant, and will take half the amount of time to make an attack. This however does not affect the Tentacle attack from Tentacle Smash Tentacle Smash.

Illaoi's ult gives her that insane 2v1 potential once you hit 6. Once you are 6, if you hit an E you generally have kill pressure if you have poked your opponent down in lane with Q which you should. Practice your R>W timing in practice tool as you should instantly W once you R. Focus on centering yourself between as many enemy champions as you can so you proc more tentacle spawns. Keep in mind your R also works with tentacles you already have spawned, so try to work it close to your current spawns.

Conqueror

This rune gives us a ton of healing and extra AD both very good stats on Illaoi. We can proc it many times with our ult combo and spamming W.

Presence of Mind

Presence of Mind is amazing on Illaoi because we spam mana more frequently than one would expect. E into our full combo is not cheap, especially if we miss E. So the mana we can back from poking down with Q is incredibly good.

Legend: Tenacity

Illaoi doesn't really need attack speed from the skill tree so tenacity is our best option. Great for late game split pushing or 2v1 or 3v1ing.

Last Stand

Illaoi is very good at staying low HP in team fights and healing back up with her kit. Last Stand is the best choice for this reason, we're going to be low HP pretty often when going in or getting ganked in 2v1 or 3v1 situations.

Bone Plating

I find resolve secondary too good not to take on Illaoi. We are going to be trading A LOT in lane and bone plating reduces a lot of damage from this.

Demolish

Illaoi excels at split pushing and breaking turrets, demolish just makes us stronger at that so we always want to pick it up. If we're left alone in the side lane we can take turrets very easily.

Teleport

Best summoner on Illaoi. Great for splitting, getting back to lane if you get camped pre-6, and getting to team fights later.

Barrier

This is a greedy summoner for Illaoi but decent and focuses on winning your lane. Great for baiting fights when you are 2v1 and tricking opponent into overcommitting. I recommend TP instead but this can work if it feels better for you.

Iceborn Gauntlet

Such a good item on Illaoi, by far the best mythic to take every game. The slow procs on your W and traps the enemy in taking more damage from your tentacle procs. Also great defensive item with resistances that make you a bigger threat when the enemy tries to all in. Best mythic for illaoi in every game.

Hullbreaker

Illaoi thrives in the side lane on her own and not so much team fighting. This item makes you a stronger threat when the enemy comes to you to stop your split. Excellent for taking turrets and fighting 2v1, 3v1, etc.

Pre iceborn gauntlet your main trading pattern will be:

Q to poke down opponent in lane, then E>W>Q as you hit it. Practice hitting E as it is so important for Illaoi's overall DPS.

Post iceborn gauntlet combo:

W>E>R>W>Q

Iceborn slows the enemy and makes landing an E WAY easier. Use this combo to jump the enemy, soul rip them, then kill them.

Will add more details with indepth videos on my guides soon! Stay tuned