Senna Build Guide : "First rule to being a sentinel...." S12

INTRODUCTION

BUILDS

CHAMPION

GAMEPLAY

- Vision Control(WIP)
- Laning (WIP)
- Late Game(WIP)

I began playing League of Legends since early season 6 (primarily on the North American, Korean and Oceanic servers), while playing competitively for the first time in season 9. I was introduced to Senna when she was revealed live on the PBE servers and she quickly became one of my pocket picks.

Of course, I'm still searching for new builds/items that might work well with her, so I'm constantly learning as I write this guide. I hope you learn something new while reading as well!

Disclaimer !
i) This guide will most likely look awful and be hard to read if you are a mobile user (since it has been written and formatted on a laptop). For the best reading experience, please refrain from viewing this on a mobile device.
ii) I'd like to emphasize that this is solely based off my insights and personal experiences in the bot-lane, so some of the information in this guide may or may not be relevant to you. This guide lacks credibility since I am, after all, low-elo. Additionally, I will unfortunately only be covering the supportive side of Senna and how to play her as the role of a support if you haven't read already. I apologize if this does not contain information regarding other roles Senna can play. This is also my first guide, so feedback is very much appreciated.

Some content may be missing because this guide is still a minor work-in-progress.

REASONS TO PICK SENNA!
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AS OF RIGHT NOW, I find her gameplay addicting and thoroughly enjoyable, however there are several other aspects to her that make her a good pick. Senna is an eccentric marksman/enchanter hybrid designed specially in a way for her to be versatile to building both damage, support or a fine blend of both. She does great deal of damage while providing utility in her kit, making her viable in a variety of roles that other champions may not be as flexible to. Although she is strong as a support, her potential as a bot laner is often overlooked when she does in fact scale equally as well. If you are new to the game, or even a returning veteran, I would always recommend adding Senna to your champion pool because she is easy to learn, strong and overall satisfying to pick.

PROS

+ Scales infinitely as time goes on
+ Global AoE shield/execute
+ Team Camouflage
+ Decent healing
+ Reduced cooldown on with autos
+ Basic kit, easy to master

Senna is still currently very strong to play. She's considered as a "secondary ADC" on the team due to , which also deals a percentage of the target's current health. Whether you choose to build complete support/damage her heals with , regardless, remain helpful amongst your team. Not to mention, she can camouflage your entire team for unexpected roams or flanks with !

CONS

- Cannot peel
- High mana costs
- Requires good positioning
- Weak heal early
- High CD timers, especially for
- Does not have an escape

Senna also does take some getting used to, especially with her very high mana costs (making heals not worth spamming in lane and her slow attack-speed. This also makes it difficult to kite, thus making positioning very important to Senna's playstyle so you can abuse her range and support your team from the back-line. With time and practice, Senna's weaknesses will become much easier to play around.

I only want to highlight a few parts that are core and compliment her set of abilities the best. The rest is mainly personal preference, whether you'd like to go into hybrid, full-damage or support. This should just be used as a general guideline as to what you want to take. As of right now (S12), the most common runes to run are Fleet Footwork, Grasp of the Undying, First Strike, and Dark Harvest. I've currently added both Summon Aery and Guardian to the rune section because I have seen a few situational builds involving enchantress Senna.

Would also love to kindly note that I categorize runes as "major" or "minor" depending on the flexibility of the pick. For example, the Inspiration tree has a lot of situational picks, thus why a lot of your options are "minor", whereas your options in the Domination tree are much more limited, so options there are "major".

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KEYSTONE
- is currently the most popular rune for good reason as it has excellent synergy with , enabling Senna to harvest souls easily while remaining relatively healthy in lane.

SECONDARY
- The most preferred secondary tree is due to its adaptability. You can really tailor to your needs with options like , and , depending on how behind/ahead you are. For a slightly more utility-focused route, I would take the tree for runes like , or even if I know I'm going to struggle in lane and need to play more defensively.

- Support or damage, your offense/flex/defense will be either attack speed, adaptive force and armor or two adaptives and armor. You can take if you feel that your cooldowns are too long, it synergizes well with so that you get 6% cooldown reduction in the early levels.

KEYSTONE
Fleet Footwork: Fleet Footwork when fully energized, heals you for a small amount and gives a short burst of movement speed. As stated previously, it enables you to stay relatively healthy in lane and even help with trading early on.

MAJOR RUNE
Presence of Mind: I have been experimented using this rune instead of Perfect Timing and have found that it is indeed a good pick. The movement speed bonus is really nice and will always be beneficial to Senna because she is squishy and has no escape. I think Perfect Timing isn't that good because I personally don't find the right time to use it and the selling value is only 20 gold.

MAJOR RUNE
Legend: Alacrity: This is just so you have a little more attack speed, as Senna's attack windup is considerably slower than the average carry. The other option here would be Legend: Tenacity if you feel that you are more susceptible to heavy CC.

MINOR RUNE
Cut Down: Cut Down is my preferred choice here, although generally speaking Coup de Grace is the stronger out of the two. My reason for this is because most champions will have more maximum health than Senna will, and it really helps against comps with a lot of tankiness. If I definitively know that I can snowball the lane or if the enemy team is much squishier than my own, Coup de Grace would be my go to.

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KEYSTONE
- has recently surfaced as a new Senna build centric around extra survivability for Senna. It is used as a tool that amplifies Senna's crowd control ability. I've recently been experimenting with this keystone and I have to say, it can be useful in many scenarios, unlike which essentially does the same thing, but sacrifices your ability to endure fights.

SECONDARY
- There are various secondary trees you could go for depending on your playstle, but is most commonly taken for which aids you in your mana hungry issues, along with or . I personally prefer and , however, you could also go for since this requires you to build . This is a really adaptable build dependent on your matchup and your own playstyle.

- Support or damage, your offense/flex/defense will be either attack speed, adaptive force and armor or two adaptives and armor. You can take if you feel that your cooldowns are too long.

KEYSTONE
Grasp of the Undying: This is taken preferably in team comps that do not favor Senna (e.g. vs. Thresh, Pyke, engaging supports), however you can also take this in every and any matchup. It is made to counter Senna's biggest weakness, which is her squishiness, whilst reinforcing her ability to put out CC. She can then resume applying her presence in lane, making her strong like she was before. The downside is she doesn't deal as much damage, but it is still worth at least trying out since it's very consistent in spite of this. I'd like to highlight that the whole point of Grasp of the Undying is building health since you now deal damage based on your health. Lethality should never be your priority when trying this build.

MAJOR RUNE
Font of Life: is my go-to when I decide to play this build, because it is the only rune that I see beneficial for Senna, since Demolish is not all that helpful in my games, and Shield Bash can't really be utilized unless you use Dawning Shadow which wastes the rune's potential. There's no real explanation to this, it's just overall beneficial for your team, especially if you land a good root.

MAJOR RUNE
Bone Plating: Whenever I go the Resolve tree, I tend to go for Bone Plating since it is overall good rune that can prevent you from losing major trades early on or getting 3-shot in both engage match-ups and matchups against enchanters. Conditioning is not all that helpful even if you're going tank, because you don't need the extra armor. Second Wind in my opinion is not really worth taking because you can always heal back with Piercing Darkness or Biscuit Delivery.

MINOR RUNE
Revitalize: this is such a good rune. I think that the small percentage buff to your heals is really good and the rest of the runes just don't compare. Please just take this, it will make your life easier. The alternative would be Overgrowth, which adds on to your health meaning you can soak up more damage and also deal more damage with Grasp of the Undying.

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KEYSTONE
- was incredibly popular amongst Senna players at the start of the season, and has now shifted to a lesser popular keystone due to its nerfs. As of right now, is not in a great spot however provides a bit of gold income that Senna really lacks and therefore is still somewhat viable.

SECONDARY
- This is mainly based on personal preference. secondary works very well because now that you have a slow in your abilities, you can harass even more with , or get some cooldown reduction with . could also work because of and , or even for sustain. Personally, the strongest runes here would be under the tree, where you pick between , , , and .

- Support or damage, your offense/flex/defense will be either attack speed, adaptive force and armor or two adaptives and armor. You can take if you feel that your cooldowns are too long, it synergizes well with so that you get 6% cooldown reduction in the early levels.

KEYSTONE
First Strike: Gives you money!

MINOR RUNE
Magical Footwear: I have been experimented using this rune instead of Perfect Timing and have found that it is indeed a good pick. The movement speed bonus is really nice and will always be beneficial to Senna because she is squishy and has no escape. I think Perfect Timing isn't that good because I personally don't find the right time to use it and the selling value is only 20 gold.

MINOR RUNE
Future's Market: Biscuit Delivery since it provides some extra sustain in lane to keep you healthy, and adds to your maximum mana pool which Senna greatly benefits from. Since you do not have sustain aside from Piercing Darkness, Biscuit Delivery nullifies the issue since it has very good potential in early levels. I take Future's Market on a lot of supports otherwise when I come across the Inspiration tree because supports struggle with gold income, even with changes to the support items so that we don’t need to upgrade our item with gold. Future's Market is also handy if you are behind in lane, because you can always go in-debt, but I still think Biscuit Delivery is currently the best option. Either of the two are situational. Minion Dematerializer is completely useless to you because you won’t be taking Steel Shoulderguards to execute minions, nor will you be trying to farm minions.

MINOR RUNE
Cosmic Insight: Cosmic Insight is usually my go-to rune to finish off the Inspiration tree, since it grants you ability haste on summoner spells and items.

Barrier

- is a really underrated summoner spell that can save you in a fight or from a bad trade. If the enemy support takes (which is likely in most games), you'll be able to negate some of the tick damage with without having to burn your carry's to save your life. The cooldown is also relatively short compared to the other summoner spells viable.

Exhaust

- is a useful defensive summoner spell used to negate burst damage from an assassin/damage composition, such as when a decides to cast , or when uses right before . While it does have a slightly longer cool-down than , is also much more effective on Senna due how it reduces 40% damage reduction from the target as well as its casting range.

Ignite

- gives early lane kill-pressure and reduces healing and is useful if you play very aggressively. It's good against squishy and/or healing champions, such as , , , , etc.. It falls of late-game but can still be used if you for some reason cannot buy an .

I do not update abilities because it is cumbersome, so if some of the information is wrong, it is simply because I just copy these from the description. Please hover over each ability if you are unsure of whether or not everything is up to date. As of now (10.23), I have updated everything accordingly.

Absolution (preview) (Passive)

COOLDOWN: 6/5/4 seconds on each target at levels 1/6/11

INNATE - WEAKENED SOUL: Senna's basic attacks on-hit and damaging abilities on enemy champions apply Mist for 4 seconds, refreshed to 0.75 seconds if Senna starts winding up a basic attack on them. If Senna applies Mist to the same target twice, she collects it, dealing 1% − 16% (based on level) of target's current health Attack damage bonus physical damage, and making the target immune to further Mist applications for a few seconds. Champions and large monsters that die near Senna spawn a Mist Wraith for 8 seconds. Epic monsters spawn 2 Mist Wraiths instead. Minions and lesser monsters have a 22% chance to spawn Mist Wraiths, which is reduced to 8.33% chance on those that Senna kills. Senna can basic attack a Mist Wraith to destroy it, gaining 3 gold and collecting its Mist.

INNATE - ABSOLUTION: Each stack of Mist grants Senna 0.75 bonus attack damage. For every 20 stacks, Senna also gains 25 bonus range and 10% critical strike chance. Upon exceeding 100% critical strike chance, Senna converts 35% of the excess into life steal.

INNATE - RELIC CANNON: Senna's basic attacks deal 20% bonus physical damage on-hit and grants 10 / 15 / 20% of the target's movement speed as bonus movement speed for 0.5 seconds on-hit (level 1/6/10).

Piercing Darkness (preview) (Q)

RANGE: 600-1300 (Based on Mist)
COST: 70 / 80 / 90 / 100 / 110 mana
COOLDOWN: 15 seconds

After a brief delay, Senna fires a spectral laser in the direction of the target unit, healing herself and allied champions in a line for 40 / 70 / 100 / 130 / 160 (+0.4 per bonus attack damage) physical damage. Allied champions hit are healed for 40 / 60 / 80 / 100 / 120 (+0.4 per bonus attack damage)(+25% of ability power) health.[/size]

Upon struck, enemy Turrets, Wards, Absolution Mist Wraiths and any other attack-interactive units are considered basic attacked once, while champions and Turrets take on-hit effects (with all turret-specific rules applied). 
Basic attacks reduce Piercing Darkness' cooldown by 1 second.
Effect radius of 1300.

Last Embrace (preview) (W)

RANGE: 1175
COST: 50 / 55 / 60 / 65 / 70 mana
COOLDOWN: 11 seconds

ACTIVE: Senna throws a globule of Black Mist in the target direction, dealing 70 / 115 / 160 / 205 / 250 (+ 70% bonus AD) physical damage and sticking onto the first enemy hit. After a 1 second delay or when the target dies, the Black Mist spreads out of the target, rooting them and nearby enemies for 1.25 / 1.5 / 1.75 / 2 / 2.25 seconds.

Effect radius of 280.

Curse of the Black Mist (preview) (E)

COST: 70 mana
COOLDOWN: 26 / 24.5 / 23 / 21.5 / 20 seconds

ACTIVE: Senna surrounds herself with an aura of mist and gains camouflage for 6 / 6.5 / 7 / 7.5 / 8. Basic attacks and abilities briefly remove the effects of camouflage.

WRAITH FORM: Gain Camouflage. WRAITH FORM: Gain camouflage. Enemies will gain obscured vision of Wraiths moving outside of the mist. Performing a basic attack or casting an ability removes Wraith Form, which cannot be regained for 2 seconds. Senna and allies camouflaged by Curse of the Black Mist also gain 20% bonus movement speed.

Effect duration of 6 / 6.5 / 7 / 7.5 / 8.
Effect radius of 400. 
Camouflage detection radius at 280.

Dawning Shadow (preview) (R)

RANGE: global
COST: 100 mana
COOLDOWN: 160 / 140 / 120 seconds

ACTIVE: Senna reveals herself before firing two beams of spectral light in the target direction, granting sight of the area briefly along its path. The center beam deals 250 / 375 / 500 (+ 100% bonus AD) (+ 50% AP) physical damage to enemy champions hit and afflicts them with Mist.

The broad beam shields Senna and allied champions hit for 120 / 160 / 200 (+ 40% AP)
(+ 1.5 per Absolution Mist collected) over a 3 second duration.

Cast time of 1.3.
Width of 320 / 2400. 
Speed of 20000, it casts instantaneously.

Senna is a relatively laid-back champion who isn't mechanically demanding, making her perfect for those of us who have slow reaction timers.

I will only be going over simple combos and a few tricks because of so.

Interactions: Piercing Darkness
It auto-locks on a target, meaning that you can cast Piercing Darkness and Flash safely out of combat to heal or execute an enemy.
Piercing Darkness can be used to clear wards or be cast on wards. The warding mechanic in which you place a ward in the middle of your casting range to extend the Piercing Darkness range is very useful.
Piercing Darkness can be used on jungle plants. The warding mechanic still applies, however using Piercing Darkness on Scryler's Bloom requires vision over Scryler's Bloom, or it will not detonate.
It can also be cast on different things, such as Mist Wraiths from Absolution, Zyra's plants from Garden of Thorns / Rampant Growth, Jarvan IV's flag from Demacian Standard, Jhin's traps from Captive Audience etc.
If there is an ally in the middle of a turret, you can use Piercing Darkness to attack the turret.
Yasuo's Wind Wall does not block Piercing Darkness because it is a laser.
An auto-attack followed by Piercing Darkness and another auto-attack procs Press the Attack because Piercing Darkness counts as an auto-attack.
The cast time is relatively slow as it is dependent on your attack-speed. When Senna dies, even if Piercing Darkness is in the middle of an animation, it will not proc.

Interactions: Last Embrace
You must Flash after casting Last Embrace for it to go in the desired direction. Otherwise, it will be cast in accordance to the direction you used Flash.
When you cast Last Embrace on a minion and it kills it, enemies within the radius are rooted instantly and there is no delay. For enemies like Yasuo, regardless if he uses Sweeping Blade or not, he will be rooted in place.
Flash Last Embrace is a good combo that raises your chances of rooting the enemy because it is less predictable and leaves little time for a reaction in between the casting.

Interactions: Curse of the Black Mist
This is not an escape tool, but more-so a disengage tool.
When you are revealed (whether through Scryler's Bloom or a Control Ward), your camouflage is disabled, however the movement speed buff still remains active.
You can use Curse of the Black Mist to detect Control Wards because it disables your camouflage. This also works for enemy champions, however it is close to face-checking so I wouldn't recommend this.

Interactions: Dawning Shadow
Much like Ezreal’s Trueshot Barrage or Jinx’s Super Mega Death Rocket!, you can use your ultimate and flash in a different direction if you are in a dangerous spot.
Yasuo’s Wind Wall blocks Dawning Shadow because it counts as a projectile.
Dawning Shadow will not hit an ally trapped in Mordekaiser's Realm of Death.
Dawning Shadow only deals damage to champions and has no effect on monsters at all. Casting Dawning Shadow for a dragon steal is a huge waste, unless you can pick up a kill on an enemy champion or if you need vision. Be wary of when to use Dawning Shadow because the cooldown is not very forgiving.

Your primary combo includes auto-weaving after every ability. I think it is the most effective way to play Senna with this strategy because she deals plenty of damage with her autos, you can cancel the animation of Piercing Darkness through doing so, and you can lower the cooldown on Piercing Darkness which you'll most likely be spamming in fights.

A > Q > A

Early Trading

is a really cool ability because it lets you cancel the animation so that you can sneak an extra auto in. An auto-attack followed by a enables you to collect a mist stack from , while also winning the trade ( here gives a small amount of burst while using this combo).

W > A > Q > A

Early Rotation

When you land a , this will be a good chance to engage on an enemy. This is basically the first combo but only added with . You can also use for a disengage, however I think that this wastes too much mana and you can get away with the movement speed collected after .

W > A > Q > A > R

Full Rotation

The same combo as before, now added with for the execute. If necessary, you can auto-weave after using . This is also your most common go-to in fights.

Q > R > F

Execution

This is a play with less functionality, but it looks cool and is nice for styling on your enemies. It is for the purpose of executing only, however in this case you will also be able to collect an extra Mist stack before they die.

A > R > F

Quick Execution

This fast combo may work when you are low on health and can fight the assassin who is chasing you. This makes use of the animation cancelling mechanic from Senna's . Unfortunately, it doesn't let you collect the Mist stack from , but it's still worth learning.

In summary, the current best Mythics are Kraken Slayer (from the currently trending build, Eclipse, Divine Sunderer and Iceborn Gauntlet. Manamune is now a pretty good buy, while Sheen items are not worth investing.

+ To Buy
This will outline several core items that are worth purchasing and give you advice on how to build Senna.

Spectral Sickle
is the AD equivalent of , which was previously built on Senna prior to the passive change. It is also the only gold income item that you will be buying.

Boots of Speed
Boots tend to be very situational that there really isn't one boot choice that you must consistently stick to. For example, vs a heavy mage team comp, you'd want to buy , and if their ADC is fed, you'd want to buy .

Boots of Swiftness
These are the most commonly upgraded boots for good reason. They provide slightly more speed than the rest of the boots and reduce slows on movement speed. Additionally, they are relatively cheap, meaning that you can upgrade your boot tier early on for an advantage against your enemies.

Ionian Boots of Lucidity
I usually suggest building if you are building full support, because these synergize very well with from the tree because of the ability haste gives. This combined with also reduces the cooldown on your summoner spells by 15% total. ]I've found buying overall the best boot choice because Senna benefits greatly from ability haste.

Boots of Mobility
allows you to roam pretty easily early-mid game. I no longer build unless I am far ahead and planning to roam (if so, I sell these for after 20 minutes.) It's just too situational.

Manamune
Previously, was slightly costly, however with the changes made with I think that it is a viable item, as you can easily stack tear and buy incredibly early on. Insanely good buy and definitely worth investing.

Frostfire Gauntlet
Good investment if you are going the build. I personally do not like it as much after the nerf.

Serrated Dirk
This item is still strong for Senna, especially if you want to go the lethality build. It builds into a multitude of lethality items that you can choose from: , , , , , and .

Duskblade of Draktharr
's passive has been updated so that it is now a must-have on most assassins. I think that it is a great item if you are snowballing on Senna support and for the most part remains a 4fun item. It is very situational, and because you can only buy one Mythic item now, its potential is immensely wasted and you would benefit significantly from different Mythics.

serpent's

Serpent's Fang
After the buffs, Serpent's Fang is a remarkably strong item, especially vs champions with lots of shields like or .

Eclipse
is the most consistent Mythic item for lethality Senna.

Edge of Night
, is honestly severely underrated and a good kind of situational, making it a good buy whether you're behind or ahead. You get a fair amount of AD and lethality, but more importantly, the free spell shield that refreshes every 40 seconds. Because Senna doesn't have an escape, this could save your life from a deadly engage.

Black Cleaver
This item is viable, but I would not really recommend it if you are not facing tanks. The only reason you should be purchasing this is if you are against a team with a lot of armor (which, in that case, you should also opt for .

Rapid Firecannon
I find that this item is rather useful in my games, since it allows Senna to poke a little further.

Most of what Senna builds are to either take advantage of her strengths (such as her range and damage), or to make up for her weaknesses (squishiness). While I cannot tell you what to build every game, my biggest pointer would be to see whether or not you are actually benefiting from the purchase, since situational items could really change the course of your game.

Vision Control

"First rule to being a sentinel...." S12

"First rule to being a sentinel...." S12

Recommended Items

Runes: FLEET

Spells:

Barrier

Flash

Flash

Ignite

Exhaust

Flash

Flash

Heal

Items

Ability Order

Absolution (PASSIVE)

Piercing Darkness (Q)

Last Embrace (W)

Curse of the Black Mist (E)

Dawning Shadow (R)

Threats & Synergies

Nautilus

Sett

Leona

Jhin

Pyke

Swain

Caitlyn

Xerath

Samira

Blitzcrank

Pantheon

Zyra

Lulu

Vel'Koz

Ashe

Brand

Morgana

Alistar

Kai'Sa

Zilean

Nami

Thresh

Yuumi

Aphelios

Bard

Draven

Miss Fortune

Kalista

Shaco

Ezreal

Soraka

Karma

Veigar

Lux

Janna

Sona

Rakan

Teemo

Braum

Seraphine

Kog'Maw

Fiddlesticks

Corki

Rell

Jinx

Xayah

Annie

Lucian

Tahm Kench

Jhin

Ashe

Yasuo

Jinx

Irelia

Caitlyn

Tristana

Miss Fortune

Kalista

Twitch