Hi! My name is Best Lulu NA. You might be wondering, why am I making a guide about Sion with my name? Since patch 7.9, Lulu has been pretty much been banned (at least in Plat and Diamond). To accommodate, I started playing a lot of other champions like Bard (check out my Bard guide) and Galio support (guide coming soon). At the moment, I am Diamond 5, hovering around 50LP.

Sion has always been known as the tanky, CC god. Oftentimes you'll see him in the top lane, mostly due to the concept that Sion needs farm to gain more HP from his W. But since his W also provides HP based on kills and assists, Sion can do just as well in the bot lane, peeling and engaging for his team. He offers tons of CC with his Decimating Smash and Unstoppable Onslaught. Chaining his R and Q allow for a total 4 seconds of CC (depending on how long Sion charges his Q and R). His Soul Furnace also provides a massive shield and bonus HP to increase his tankiness and chances of survival. His Roar of the Slayer helps his ADC due to the 20% decrease in armour and 40% slow.

Funny enough, Sion got me to Diamond. I spammed him all through Plat 1 after my Galio spam (which got me from Plat 2 to Plat 1) wasn't working. I currently hold a 78% winrate with Sion and a 63% winrate with Galio.

Pros
-Tons of CC
-Does a lot of damage
-Great roamer with Unstoppable Onslaught
-Can tank a lot of hits
-Can set up ganks quite easily
-Cheeses pretty easily

Cons
-Kinda weak until he buys Locket of the Iron Solari and a health item
-Can be kited by champs like Vayne
-Susceptible to early poke
-Abilities are somewhat difficult to hit with new players

Red Side
-Make sure you have an early game ADC like Draven, Lucian, Caitlyn (with traps), or Twitch.
-Take Ignite (not necessary but very helpful)
-Ask your jungler to start at Red Buff
-Sit in the botlane river bush until 1:30
-Move into their tri bush
-Wait for the enemy botlane to face check when coming to lane
-Q while they approach
-Kill them

Blue Side
-Make sure you have an early game ADC like Draven, Lucian, Caitlyn (with traps), or Twitch.
-Take Ignite (not necessary but very helpful)
-Ask your jungler to start at Blue Buff
-Sit in the botlane tri bush until 1:30
-Move into the bot lane river bush
-Wait for the enemy botlane to face check when coming to lane
-Q while they approach
-Kill them (Not as good on blue side since there are two ways in)

Honestly, it's pretty simple. The only thing to account for is possible escapes that certain ADCs have (besides Flash) like Vayne's Tumble. Often coming at an angle makes it harder for enemies to dodge your ult since you tend to split up the entire team when doing so.

Here's a video on how to ult in the jungle and more easily control your ult Play Video

Flash - Self explanatory

Exhaust - I take this against most match ups. Normally I take it against hard carry early game ADCs like Draven. I also take it against dive comps.

Ignite - I take this when I know we can fight early game or against weak champions like Ezreal and Vayne.

Eye of the Equinox - I only take this over Face of the Mountain because of item space. FOTM isnt too practical because normally you are miles away from your ADC during teamfights.

Ninja Tabi - I take this against heavy AD comps

Mercury's Treads - I take this against heavy CC or AP comps

Locket of the Iron Solari - A must have item on Sion due to the most recent change, making the shield it grants based off of the user's bonus HP.

Gargoyle Stoneplate - Works wonders with Locket of the Iron Solari because of its active. Since it increases your maximum HP by 40%, it makes the shield from Locket of the Iron Solari enormous.

Spirit Visage - I only take this against fed mages

Redemption - I take this against AOE comps

Warmog's Armor - I take this most games for its CDR and extremely high bonus HP increase. The regen effect allows Sion to constantly all in and back off with ease.

Knight's Vow - I dont normally take this unless the enemy has a dive comp

Zz'Rot Portal - Only good against split comps

Frozen Heart - I take this most games due to the 20% CDR, 400 mana, and massive amount of armour this item gives. Buying it along with an HP item that gives CDR, you can hit 40% CDR very easily.

Randuin's Omen - I only take this if I have to buy an HP item that does not give enough HP

Glory in Death -
Upon taking fatal damage, Sion briefly becomes untargetable and enters a frenzy, restoring himself to 100% maximum health but losing 2 - 19 (based on level) every 0.25 seconds, increasing by 1.4 - 13.3 ( based on level) per subsequent tick.
Sion can freely move and use basic attacks during this time, gaining 100% life steal, attacking at 1.75 attack speed, and dealing 10% of target's maximum health as bonus on-hit physical damage, capped at 75 against minions and monsters.
While Glory in Death is active Sion's standard abilities are replaced with Death Surge

Death Surge -
ACTIVE: Sion gains 50% bonus movement speed that decays over 1.5 seconds.

Sion's passive, although not my favorite, is pretty fun to use. I've garnered quite a few kills after dying. People tend to underestimate how useful his passive is during teamfights, often walking a little too close, allowing him to reign hell upon them under his fists of fury.

Decimating Smash -
FIRST CAST: Sion channels for up to 2 seconds in the direction of the mouse cursor, increasing Decimating Smash's damage over the duration (up to 300%) and its range over the next second. If the channel is interrupted, Decimating Smash goes on a reduced 2 seconds cooldown.
MINIMUM DAMAGE: 12 / 24 / 36 / 48 / 60 (+ 39% AD)

SECOND CAST: Sion flails his axe, dealing physical damage to all enemies in the target area, increased by 33.3% against monsters and 66.7% against champions, and slowing them by 50% for 0.25 seconds.
MINIMUM MONSTER DAMAGE: 16 / 32 / 48 / 64 / 80 [/color
(+ 52% AD)
MINIMUM CHAMPION DAMAGE: 20 / 40 / 60 / 80 / 100 (+ 65% AD)

If Decimating Smash was charged for at least 1 second, Sion instead slams his axe down, knocking up all enemies hit for 1.25 - 2.25 seconds, based on how long Decimating Smash was channeled.

I like this ability due to the fact that when channeled in the fog of war, Decimating Smash's indicator is invisible. It also has enormous damage early game, averaging at about 200 damage at level 1 when fully charged. I max this first for its increased amount of damage and lowered cool down.

Soul Furnace -
PASSIVE: Sion permanently gains 2 bonus health whenever he kills an enemy, increased to 10 bonus health against large enemies and enemy champion takedowns.

FIRST CAST: Sion shields himself for up to 6 seconds. After 3 seconds, Soul Furnace can be reactivated to detonate the shield, detonating automatically if it persists for the full duration.
SHIELD STRENGTH: 30 / 55 / 80 / 105 / 130(+ 40% AP) (+ 8 / 9 / 10 / 11 / 12% maximum health)

SECOND CAST: Soul Furnace's shield detonates to deal magic damage to enemies around Sion, capped at 400 against minions and monsters.
MAGIC DAMAGE: 40 / 65 / 90 / 115 / 140 (+ 40% AP) (+ 10 / 11 / 12 / 13 / 14% of target's maximum health)

This ability allows Sion to indefinitely scale. Late game, I normally have an average of anywhere from 300-600 bonus HP due to Soul Furnace. This ability also does a surprisingly large amount of damage due to its percent damage at max rank. I max this second for the increased shield and damage.

Roar of the Slayer -
ACTIVE: Sion bellows in the target direction, dealing magic damage to the first enemy hit, slowing them as well as having their armor reduced by 20% for 2.5 seconds.
MAGIC DAMAGE: 70 / 105 / 140 / 175 / 210 (+ 40% AP)
SLOW: 40 / 45 / 50 / 55 / 60%

If the target is a minion or non-epic monster, they are knocked back 775 units, dealing 30% increased damage to all enemies they pass through and Slow icon slowing them by the same amount for 2.5 seconds. Projectile enemies stop upon colliding with terrain or reaching the end of their trajectory.

This ability allows your ADC to pound away at the enemies. It is also not a bad way to shove a wave and poke down enemies. I max this last since the armour shred does not stack.

Unstoppable Onslaught -
FIRST CAST: Sion charges in the target direction for up to 8 seconds, during which he cannot cast abilities nor attack, but is immune to all crowd control. Sion's trajectory updates itself toward the cursor over the duration, but his capacity to change directions is reduced.

SECOND CAST: Sion halts his charge and slams the ground after a brief delay, dealing physical damage to nearby enemies and enemy turrets. If Sion stops directly in front of narrow terrain, he dashes over it.
If Sion collides with an enemy champion, structure, terrain, or charges for the full duration, he slams the ground, dealing physical damage to nearby enemies and turrets, briefly stunning himself for structure and terrain collision.
MINIMUM PHYSICAL DAMAGE: 150 / 300 / 450 (+ 40% bonus AD)

Damaged enemies are slowed for 3 seconds, and those Sion directly collides with are also pulled into him as well as stunned for 0.75 seconds.
SLOW: 40 / 45 / 50%
Unstoppable Onslaught's damage and stun duration increase over the charge's first few seconds, capping at 200% damage and 1.75 seconds, respectively.

This ability is extremely fun to use. Its potential to start and end teamfights from extremely far away allows Sion to freely push other lanes or bait the enemies into fights.

Overall, I believe Sion is a resident sleeper pick that has yet to seen the light of day. His outstanding performance in the mid to late game allows him to demolish teams with his massive amount of CC and damage absorption.

July 2nd, 2017 - Guide posted