Hi everyone. I'm TheMistCollector, TMC or Mist for short. I am a multi-season challenger Senna OTP who has been playing this champion non-stop ever since her PBE release. Although I don't have a dedicated account for each of her roles, I've played ADC, Fasting and primarily support hundreds of games each at a high-elo level, and I'm here to give you a complete guide on how to use this champion the way I do, which has bringed me a lot of success.



Before Senna, I was a Support main, but i've always enjoyed Marksmen playstyle. When Senna got revealed, i knew she was my champion. I was there day 1 analyzing and theorycrafting with Senna, along with others... So yeah, i feel like i really know about this champion.

Btw this is my first time making a guide, so sorry for any inconsistencies and for no fancy table of content and all of that.

THIS GUIDE WILL GET CONSTANTLY UPDATED, any big change that affects Senna will be addressed. Additionally, i'm constantly theorycrafting new items and builds, if i find something OP, i will share it.

Also, english is not my main language, so if you don't understand a section of the guide or you find a small typo, please let me know!

(Apologies for the format getting kinda messy towards the end of the guide for mobile users).

You can spy my match history here:

Most active account:

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First Account:

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First of all... What does Farming and Fasting even means?!

Farming/ADC

This is your conventional ADC strat. You start normal ADC item, with a normal Support, you farm minions, take kills... Just as a normal ADC, nothing weird here. Throughout this guide i will be using both "FARMING" and "ADC", just so you know that i'm talking about the same thing.

Fasting

This is an alternative strat that revolves around Mists. You go Support item first, and your duo (non-marksmen) farms with normal starting item. This strategy allows Senna to "protect" her duo by poking so they can farm safely, while she gets fed with Mists and kills. Suddenly in late game, you have a champion with crazy DPS and tons of utility (almost covering both ADC and support role), and another champion with good damage and utility. Senna can take 1-2 melee minions per wave to reach her maximum potential. Minion gold, Support item gold, and Mists crazy gold efficency make this strategy so good.

PROS

• Mechanically simple champion
• Easy to learn
• Infinite scaling
• Playstyle versatility
• Skill expresion
• Uniqueness in both gameplay and builds
• Annoying to play against
• Cool concept/desing

CONS

• Bad early game when farming
• Bad mid game when fasting
• Very reliant on mists (No AD per level)
• Low elo tilting when fasting
• ADCs don't like to play with a Senna support (for some reason)
• Terrible when counterpicked
• Awkward AAs with low practice
• DuoQ reliant when fasting (unless Master+)

In this chapter I will talk about the different builds you can go on Senna for each of her roles, and when to go for them. Some of the reasoning for going certain builds are tied to specific matchups, more info in the "Matchups Sheet" chapter.

ROLE: SUPPORT

Build: Bruiser

This build has a little bit of everything. You have a good early spike, with a really strong mid-lategame. You also have good short trades, good DPS, can deal with tanks, and can survive vs. assassins/divers with enough skill. This build doesn't have the snowball potential as good as Lethality, but it's still good (better than Tank for example). Go for this build when: • You're in a lane where you can't snowball • Your team needs damage but a lethality build won't be efficient because the enemy team is tanky • The enemy team has assassins/divers but also a lot of poke (so tank isn't efficient). • And/or you're unsure what to build. You can't go wrong with this build.

Build: Lethality

This build is focused on the early game. Because of the nature of the build, once mid game comes and you don't have a gold advantage, you will transition into an utility caster, utilizing your high bonus AD values to empower your team with strong Piercing Darkness' healing and slows, as well as threatening a fast burst damage with your Absolution proc combined with your passive. Don't underestimate this build though, because if you get a high gold advantage early on, you can easily take over the game with your fast spikes as long as you keep your distance. Go for this build when: • You're in a lane where you want to snowball. • You're in a lane where you need the early AD to survive vs. poke. • And/or your team doesn't need a specific build, and you don't need tankiness to survive.

Build: Tank

This build is entirely team focused. You sacrifice a lot of early game power and solo-agency for insane teamfight and peel potential later on. Your playstyle in mid-late game should be to play around a carry, and disrupt enemy assassins/divers who try to shut them down. Go for this build when: • You're in a lane where you can't snowball. • Your team doesn't need damage • The enemy team is assassin/diver heavy and you need to protect an important member of your team • And/or you can't survive with another build.

Build: True Support

This build has a similar approach as the AD Stacking build, but this one is more mid-late game focused and trades some damage for tankiness. Go for this build when: • You're in a lane where you can't snowball. • Your team doesn't need damage • And/or your team doesn't need a specific build, but you need the extra tankiness to survive.

ROLE: ADC & FASTING

Build: DEFAULT

Best in Slot. Allows to have good early game pressence alongside a good midgame transition. Go for this build when: • You can snowball. • And/or there's not a lot of tanks on the enemy team or you're not the one killing the tanks.

Build: TANK-KILLER

Simply the highest DPS build. Go for this build when: • You can't snowball and need to play the long game. • And/or you need to go with the highest DPS build because you're the only tank-killer

In this chapter i will talk about the reason behind each rune in all of her builds and how they synergize with Senna, as well as some other popular (but not necessarily good) alternatives.

Main builds:

Fasting/Farming/Support Precision

Fleet Footwork: Welcome to Cut Down meta! Fleet Footwork is the only keystone here that Senna can blindly use. It gives a MS burst which is nice for an immobile marksmen, and the heal helps her play a bit more aggresively. The main reason we go for this though is because of the access to Cut Down. In 12.12b, Senna became the champion with the lowest base HP of the game with 530 ( Yuumi has 550... 13.1b UPDATE: Good news, Senna is no longer the champion with the lowest base HP in the game, bad news, it's not because she got buffed, but because Yuumi got nerfed. Basically, her HP is still low even if it's not the lowest one anymore). Because of this, Senna is the best champion to use Cut Down, and we should always use it when building for damage.

Lethal Tempo: After the 13.4 AS ratio buffs (from 0.3 to 0.4), this rune is now viable on Senna. I'd now say she uses every on-hit effect pretty effectively including this one. She stacks it consistently and the AS she gets is pretty good. Because she already has 600 base range, once it's stacked she can easily keep hitting champions in laning phase to keep the stacks and have 30-42% AS "permanently" alongside the extra range for your Q. After laning phase, this rune also has a really good scaling so you get a lot of extra DPS. I don't think this rune is that good to completely ignore Fleet, but it's good enough to risk your laning phase to use the rune for lategame DPS. Since ADC Senna doesn't want Fleet as religiously as Support/Fasting, this will be the best Standard keystone for her.

Press the Attack: This is an alternative rune in scenarios where Fleet Footwork is not needed and you will constatly fight early 2v2s. Senna can proc this rune pretty fast with Piercing Darkness and from a safe distance to not only boost her own damage, but her allies' too.

Support Resolve

Grasp of the Undying: Default rune for the Tank build, it helps with lane pressure with its healing and bonus damage (both scaling with max HP), but the main reason we go for this rune is the infinitely stacking Health. It's just an amazing synergy with the Tank build which is mostly Health stacking.

Support Inspiration

First Strike: You may have noticed that I go back and forth between recommending Arcane Comet and this rune, and that's mostly because of the meta, I think both keystone have a place in the Lethality build depending on what is currently strong. Anyways, I currently think that First Strike is the better keystone for Lethality (when you don't need Fleet Footwork. The Econ is just too good to pass up, the Inspiration tree allows us to have a surprisingly safe early game, and once we have a couple of items, the damage this rune offers is still pretty sizable.

Popular rune choices:

Ultimate hunter: It's not worth taking it because Senna is not really reliant on Dawning Shadow. It's true that Senna's Ultimate has a lot of cooldown, but losing Precision tree for a couple more ultimates is not worth.

Triumph: Ignoring that this rune scales with Max HP (and Senna has the second lowest), it is also meant to be very Skirmish/Bruiser heavy since it allows you to sustain better throughout the whole fight. If Senna wants a defensive rune, Overheal Will be better, since it she's most likely either at full health, or dead/out of combat; you cannot afford to have survivality dependent on getting takedowns. Besdies, if you're using this row, Presence of Mind will almost always outvalue both.

Cheap Shot: While it looks good on paper, when compared to Taste of Blood you realize that the latter is better (Not by a lot, but still better). They both look to gain early advantages, one via damage and the other via healing, but ToB scales infinitely better and it is easier to proc.

Coup de Grace: Cut Down DEALS MORE DAMAGE IN 105% OF THE MATCHES AND I'M NOT ONLY TALKING ABOUT SENNA (BUT SHE'S ONE OF THE BEST USERS BECAUSE OF HER EXTREMELY LOW BASE HEALTH), BUT EVERY MARKSMAN. STOP PICKING THIS GARBAGE RUNE!

Demolish: You outrange its proc range starting at level 1, so it's awkward to use from the start. Besides, the value of Font of Life in a health stacking build is too good to pass up.

In this chapter I will talk about the reason behind each item in all of her builds and how they synergize with Senna, as well as some other popular (but not necessarily good) alternatives.

ADC/Fasting Crit Build:

Core items:

Stormrazor - Highest AD Noonquiver item, AD scaling damage.

Shiv is back at being a must-buy for most crit champs, and Senna is no exception. The fast powerspike allows you to have IE as soon as possible, and the effect itself is really strong on Senna since she doesn't have much push power early game.

Infinity Edge - High AD, better crits.

Senna has free crit, this item makes your crit strikes stronger, alongisde giving a lot of AD, it's that simple.

Opportunity - Cheap lethality.

After Youmuu's Ghostblade's nerfs in 14.3, I prefer this item as your cheap lethality option. Opportunity has always dealt more damage than it, but its added survivability + econ was better in comparison, and that's exactly what it got nerfed. This limits your ability to be a proper tank killer later in the game, so it's not built every game.

The Collector - Highest AD Noonquiver item, AD scaling damage.

Alongside Opportunity, the best 2 item powerspike. The Collector makes it so we can keep pushing our advantage with additional lethality, alongisde the crit chance that helps with a cleaner mid-game transition. This limits your ability to be a proper tank killer later in the game, so it's not built every game.

Support Bruiser Build:

Core items:

Eclipse - Cheap AD, survivability.

14.1 massively changed this item, and I think it's finally good on Senna now. It offers 70 AD for 2800 gold which is extremely good for her, and the ranged cooldown got cut in half, so it's usable on ranged champions again. Eclipse's passive damage gives decent burst, that only grows with the more items we build (because it's %current HP), so it's both a good cheap spike as well as a good late game item for short poke. The shield can also come in handy vs. assassins/divers, so as you can see this item is able to do a lot of things for just 2800g! The only weakness of this item is the stat profile, since it's *only* AD, but Senna, specially Support Senna, is more than ok with getting just AD.

Blade of the Ruined King - MORE DAMAGE

I would normally recommend Terminus here, but I'm going for a specific combo with Eclipse plus this item. These item's %current HP physical damage, combined with Absolution's %current HP physical damage makes this 2 item combo super deadly by giving us a really good burst in our starting combo, without falling down on DPS/tank-killing potential. Botrk also gives a little bit of tankiness just like Eclipse, so the shield + lifesteal makes us surprisingly hard to kill if we know how to play the fight.

Support Lethality Build:

Core items:

Voltaic Cyclosword - Best The Brutalizer item.

With the Serrated Dirk + The Brutalizer combo being so strong, Senna is also able to abuse it. This item is the only good legendary that builds out of brutalizer that she can use, so we will use it as core.

Support Tank Build:

Core items:

Heartsteel - Highest HP item

With Radiant Virtue being removed in 14.1, we're back to Heartsteel. Same principle as any item in the tank build. High HP, and/or benefits for having high HP, and this item has both.

Black Cleaver - Standard HP + AD item.

I've come around. Even if this item is bugged, the stat profile + effect is just to good to pass up, specially after the 14.1 item changes, which lowered the majority of other item's stats.

True Support Build:

Core items:

Locket of the Iron Solari - Early resistances

This is a great tank item. it's really cheap and it makes you surprisingly tanky. The active is kind of insane, and because it also affects you, that's another extra tankiness. Another important part about this item is that the early tankiness is a great way to stack Mists consistently. It allows you to go more carelessly than you normally would (remember, Senna has the lowest base HP in the game), both helping to apply pressure in the lane and scaling. Senna doesn't need to push an early lead through damage or zoning the enemy botlane like a Xerath (she definetly can and will though), she just needs to hit her targets constantly, and early tankiness works the best.

Redemption - More utility, H&S power

Best way to tie this build together. The H&S power of the item increases pretty much every everything present in our champ, inventory and runes, while offering extra long range utility to the team at a cheap price. The HP also comes in handy to further increase the efficiency of Locket of the Iron Solari's resistances.

General items:

Bloodsong - AA Quest item

The most synergistic Quest item for Senna. It greatly benefits from constatly AAing and weaving in spells, and Senna is constantly doing these things. The effectt is also currently very overpowered. Note that you can proc this from a mile away with Piercing Darkness, that's another part of it's great power on Senna.

Celestial Opposition - Vs. Assassins

Giving up Bloodsong is rough, but some matches will simply not allow you to step up and AA everyone because of the risk of getting oneshotted, so this is where the item comes in handy.

Boots of Swiftness - Standard.

Situational boots when MS will make you survive more than standard resistance boots. Either the enemy team has a lot of skillshots, or they're very melee with not a lot of ways to get on top of you.

Plated Steelcaps - Vs. Physical damage or heavy AAs.

These boots should be considered your "default". It will practically always have value inside of SoloQ, specially in the botlane. Champs like Zed, Viego, Jax, Draven Pantheon get destroyed with these boots early on.

Mercury's Treads - Vs. Magic damage or heavy CC.

These boots are great if built in the correct match, it offers a lot of resistance against AP champions, or heavy CC (example of champions that get countered by these boots: Mordekaiser, Morgana, Malzahar, Ziggs, Leona).

Berserker's Greaves

After 13.4 AS ratio buff i believe these boots are viable on Senna. They are not as amazing to drop Swifties/Plated/Mercs completely, but it is good to consider them when you need to or are simply able to give up defensive boots to deal more DPS.

Essence Reaver - Good stats with insane AD scaling effect.

Even though this item is meant to be a rush, and its quite good at that, for Senna this is an amazing item after your cores because of its AD scaling. No matter if you're building Lethality or DPS, if you build this item in mid-late game it will hit like a truck. Be aware that you shouldn't build this item alongside Bloodsong, as both are spellblade effects.

Rapid Firecannon - Vs. Gap closers or deadly skillshots, special interactions.

This item works really good on Senna. The extra range helps with early survivability and it also helps to proc your Piercing Darkness slow from a long distance. This item shines with Senna's special interaction with it: Q range and hitbox gets bigger (since they scale with AA range), and you can AA+Q combo with one RFC charge (bug? either way it has been here since Senna's release, so almost 0% chance it gets "fixed").

Hubris - Stomp.

Item is just amazing for soloQ after the 14.1 hotfix. It's a good option after your core items if you're stomping or simply want more lethality. (IMPORTANT MISCONCEPTION: Earlier tooltip descriptions of the item stated that the effect only worked on kills, but that was wrong and was corrected after some time. It actually tracks assists too, meaning that's it's also an option if you're playing support).

Blade of the ruined king - Vs. tanks.

Although i don't normally recommend Lifesteal/Omnivamp items, Botrk is just busted. You will shred tanks and get access to extra utility with the super low CD slow. It's not recommended to build it in lethality build same as Wit's End since you will not make a lot of use of the passive extra damage.

Runaan's Hurricane - Great teamfight potential, special interaction.

This is a great item on Senna. Because of her long range, it's super easy to keep firing bolts and poke the enemy team down before they can fight. This item shines against melee heavy comps. Senna's special interaction with it is insane too: Since bolts counts as AAs, they each reduce Q CD by 1 additional second (up to 3 seconds per auto attack). This helps her to deal a lot of extra damge, as well as healing a lot of extra HP.

Phantom Dancer - Runaan's Hurricane alternative.

Alternative early Zeal item where Runaan's Hurricane will not be as efficient (You don't have a great range advantage, the enemy team will not be that close together in teamfights, etc).

Wit's End - Insane survivability, cheap and good DPS.

Adapting to the meta, Senna is surprisingly a good Wit's End user. This item is really broken, it grants a lot of hybrid damage, movement speed and basically free magic resist.

Lord Dominik's Regards - Vs. Armor.

This item really helps with tanks, and it's just a generally good late build. Giant Slayer passive is great on Senna since she's the 2nd lowest HP in the game.

Mortal Reminder - Vs. Healers.

Standar anti-heal item, try to never build this if you're not playing support.

Immortal Shieldbow

Decent item if you need survivality and your team can't peel you properly. It's the best combination of a damage and defensive item.

Guardian Angel - 1st option Vs. High AD damage

The standar marksmen defensive item, it helps a lot with AD assassins because of the armor and resurrect passive.

Frozen Heart - Vs. Melee AD and AS

Great item when you need the extra survivality against AD champs yourself or as a way to peel your priority targets because of its aura effect.

Randuin's Omen - Vs. Crit or Melee AD.

Alternative AR item for when the enemy team has either a lot of crit damage, or the slow can help you survive an AD threat.

Maw of Malmortius - Vs. Magic damage.

Standar defensive item against magic damage. Magic shield scales with AD so that's a great bonus for Senna.

Anathema's Chains - Vs. 1 enemy threat

Alternative defensive item for any role if there is only 1 scary threat in the enemy team. It works great if you've built other defensive items as it only grants health.

Knight's Vow - Supportive option for specific peel

Great item for Support (Tank and Hybrid only) Senna if you want to fully play around peeling a carry.

Spirit Visage - Vs. AP

This is a great item against AP champions. It provides with A LOT of MR, plus some nice extra healing to survive almost anything.

Mercurial Scimitar - Vs. Heavy/Undodgeable CC

Standar Marksmen item against Hard/Undodgeable CC.

Zhonya's Hourglass - 2nd option Vs. High AD damage

This is an alternative to Guardian Angel. It's a little tricky to explain when to take one over the other, but the first thing i would consider is wether i can use the active before i get killed. If the enemy team's AD damage threat is really hard to react (example: Shadow Assassin Kayn), or if they have a lot of CC, i wouldn't recommend Zhonyas.

Mikael's Blessing - vs. enemy CCs (peeler version).

If your team really needs it, you can build it.

Vigilant Wardstone - Standar Supp

This is a must buy if you are the support item in your team. It solves the problem of always carrying a pair of Control Wards in your inventory, with nice stats. Also, the extra wards passive (in both inventory and map) is extremely valuable.

Elixir of Wrath - Standar.

This is the standar marksman Elixir, it gives a lot of AD, and basically free sustain because you don't need more gold at that point of the match, so that doesn't matter.

Elixir of Iron - Additional defense.

This elixir is good if there is still a champion in the enemy team who can kill you like nothing, also the additional tenacity is a nice bonus.

Popular items:

Moonstone Renewer + Staff of Flowing Water

You heal for basically the same with any other build, except that you deal almost no damage and gets one shotted. Never buy these items.

Iceborn Gauntlet

This item is no longer a good purchase for Senna, as she already has a consistent slow on her Q, buying another one is not worth it. 12.22 UPDATE: It now builds out of Sheen, it's way worse now. Never build this item.

Sheen items

Any Sheen item is bad on Senna. They all scale with Base AD (except Essence Reaver, which scales with bonus AD as well, that's why it's good on Senna), and she's stuck with 50 throughout the whole match, because of her passive. Buying a Sheen item is significantly weaker on Senna compared to every other champion. Never build a Sheen item.

Dead man's plate

Some people build this item as an alternative to Black Cleaver when the enemy team doesn't have enough armor. It looks like a good idea, but the item is generally trash, and it additionally scales with Base AD, same deal as Sheen items. Never buy this item.

Support Crit Build

The build is crazy expensive, expect to start dealing damage at +25 minutes into the match, and most matches are already decided by that point. Also, your team does not need another squishy DPS carry. Never go for this build.

Support Manamune

As i've noted in quite a lot of other chapters, Senna does not need Manamune's high mana because the support item already gives enough of it. If you build it because of the high AD, you're better with something like Umbral Glaive or Serpent's Fang. Never go for this item as support

In this chapter i will talk about the standar summoner's spells for Senna, as well as some other popular (but not necessarily good) ones.

Main spells:

Flash: This is the best summoner spell in the game, by far. It can be used both aggressively and defensively, and can be used with other abilities (mostly Last Embrace and Dawning Shadow) to create unpredictable situations for the enemy team. Not taking this summoner spell is trolling.

Barrier: This is the standar summoner spell for support, because double Heal is a bad option. it helps for general survivability. If your ADC doesn't go Heal, consider picking it if you don't need Exhaust.

Heal: This is the standar summoner spell for farming and fasting. It helps for 2v2 early fights and for late game survivability. Go for this if you don't need Exhaust or Cleanse

Exhaust: This is a good alternative. It is meant to counter assassins and skirmishers. Against these champions it's always more valuable than Heal, since it shuts down burst damage.

Ghost: Great alternative in matches where Movement Speed will make a great difference. It can be used both defensively (to disengage from a fight, to avoid a gank, etc) and aggressively (to chase down a target, to have better kite, etc).

Cleanse: This is a great summoner spell meant to counter heavy CC ( Ashe, Leona, etc.) or any undodgeable CC ( Twisted Fate, Annie, etc.). I always prioritize this over Exhaust since being CCd means that anyone can burst me down anyways. (avoid using this when playing support, unless you when don't need neither Heal nor Exhaust)

Popular spell:

Ignite: This is NOT a good summoner on Senna, doesn't matter the role. If you are at Ignite range, you are poorly positionated.

In this chapter I will show every ability of Senna, as well as giving general information and tips.

Passive - Absolution

Ability full description BASIC ATTACK: Senna blasts her target with her relic cannon, dealing 100% AD physical damage and applying on-hit effects. This attack does not use a projectile. Senna's basic attacks can critically strike, but they only deal (150.5% + 30.1% 30.1%) AD physical damage. Senna's attack speed benefits from only 20% of her total bonus attack speed (instead of 62.5%) and the attack's windup time is only reduced by 60% of the expected value given attack speed bonuses. Senna's attack windup is reduced by 100-(0.5 to 0.35)/0.5*100% (based on level). INNATE - WEAKENED SOUL: Senna's basic attacks on-hit and damaging abilities on enemy champions apply a stack of Mist for 4 seconds, modified to 0.75 seconds if Senna starts winding up a basic attack on them. Subsequent hits will collect Mist, dealing 1% − 10% (based on level) of target's current health as bonus physical damage, and rendering the target immune to further Mist applications for a few seconds. This damage applies life steal at 100% effectiveness. Enemies that die near Senna may spawn a Mist Wraith from their corpse. A Mist Wraith lasts 8 seconds and Senna can basic attack or hit it with Piercing Darkness Piercing Darkness or Dawning Shadow Dawning Shadow to kill them instantly, granting her 8 Gold 8 and collecting their Mist. Enemy champions and large monsters will spawn a Mist Wraith. Epic monsters will spawn 2 Mist Wraiths. Minions and lesser monsters that Senna kills have a 8.3% chance to spawn a Mist Wraith. Large minions that Senna does not kill will spawn a Mist Wraith, while lesser minions and lesser monsters that Senna does not kill have a 28% chance to spawn. MIST: For each stack of Mist, Senna gains 0.75 bonus attack damage. For every 20 stacks, she also gains 20 bonus attack range and 10% critical strike chance, capped at 100% critical strike chance. Additionally, 35% of the generated excess critical strike chance is converted into life steal. INNATE - RELIC CANNON: Senna's basic attacks on-hit deal 20% AD bonus physical damage and grant her 10 / 15 / 20% (based on level) of the target's movement speed as bonus movement speed for 0.5 seconds. This damage applies life steal at 100% effectiveness.

In a nutshell, Senna's auto attacks have reduced attack speed, deal reduced crit damage, doesn't use a proyectile, gives her movement speed and deal additional on-hit damage. Hitting an enemy champion with an auto attack or damaging ability 2 times grants Senna a Mist stack. Each Mist stack gives 0.75 AD, and gives 20 range an 10% Crit chance per 20 Mists (excess crit chance grants Lifesteal instead, up to 35%). Mists can also appear when a unit dies near Senna (chance is different for each unit, also affects if Senna is the killer.)

General tips:

• This is the most important ability in Senna's kit, since you don't have AD per level, it's important to have a high Mist per Minute ratio. 4 Mists per Minute (40 mists at 10 minutes. 100 mists at 25 minutes) when Fasting, and 2.5 Mists per Minute (40 mists at 16 minutes. 100 mists at 40 minutes) when Farming are good indicators that you're doing good.
  
• 40 Mists is a generous powerspike since you gain a lot of gold worth from stats (~1500 gold) and the 40 additional range makes you a much scarier threat.
  
• You can lifesteal out of Mist wraiths
  
• Ally champions who kill minions with Relic Shield or Steel Shoulderguards are considered killed by Senna for Mist Spawn Chance purposes (THIS IS CURRENTLY BUGGED AND NOT WORKING! (14.4 last seen) be sure to ask your support to take cannons!)

Q - Piercing Darkness

Ability full description ACTIVE: Senna fires a spectral laser in the direction of the target unit, healing herself and allied champions in a line, and dealing physical damage to enemies in a thinner line. Upon being struck, enemy turrets, wards, jungle plants, Mist Wraiths and any other attack-interactive units are considered basic attacked once, while champions and turrets are applied on-hit effects at 100% effectiveness. Basic attacks reduce Piercing Darkness' cooldown by 1 second on-hit.

When to use:

This is your main ability, you use it to trade, for high DPS and huge healings in teamfights. If you have enough range you can pretty much hit all 10 champions with every Q, so think about your positioning.

General tips:

• You should constantly AA anything (if minions, make sure you don't mess up the wave for your ADC) because it reduces Q cooldown, allowing you to trade more oftne
• This ability can reduce its own cooldown when used against: Enemy turrets, enemy champions, jungle plants and enemy wards, meaning if you Q into AA against any of this things you will reduce 2 seconds of cooldown in no time.
• This ability cannot reduce its own cooldown when used against: Ally turrets, ally champions, ally and enemy minions, ally wards, jungle monsters (dragons, buffs, small camps) and mist wraiths.
• If you hit your Q against both a target that reduces its own cooldown and one that doesn't, regardless of target, it will still reduce it.
• If your Q hit multiple enemy champions, it will reduce its own CD by 1 second for each enemy champion hit
• You can use Q to clear enemy wards faster
• Sheen and other on-hit effects procs based on enemy Spawn ID.
• This ability is currently BUGGED (13.19 last seen): If you use it while channeling Dawning Shadow the Q will go towards the ultimate's angle, not the Q target.

W - Last embrace

Ability full description ACTIVE: Senna throws a globule of Black Mist in the target direction that deals physical damage to the first enemy hit and sticks onto them for 1 second. After the duration or when the target dies, the Black Mist spreads out of the target, rooting them and nearby enemies for a few seconds.

When to use:

This ability is just a generic CC, you can use it to escape, lock a target, follow up a target or opening a follow up to your allies. You can also use this ability when warding to check brushes without risk.

General tips:

• You can W + Flash, the ability will be casted to target location from after-flash position. There is a bug that, when timed correctly, will make your W projectile look like its going from pre-flash position, but its hitbox is actually from after-flash position, making it look like it goes through enemies and suddenly hits a random target.
• You can look to kill a low hp minion close to an enemy champion with W to surprise them with an instant root
• Malzahar's Void Shift will block W damage, but not the root (as long as he is the main target).

E - Curse of the black mist

Ability full description ACTIVE: Senna surrounds herself with an aura of mist and gains camouflage for a duration. If Senna breaks the camouflage, she regains it after 1.75 seconds of not performing actions that break stealth. Allied champions who enter the mist gain Wraith Form for a duration equal to the remaining duration. WRAITH FORM: Gain camouflage. Enemies will have obscured vision of Wraiths moving outside of the mist. Wraith Form can be regained if lost by breaking the camouflage after 1.75 seconds of not performing actions that break stealth. Wraith Form ends immediately upon Senna's death. Senna and allies camouflaged by Curse of the Black Mist also gain 20% bonus movement speed.

When to use:

This ability is the most tricky ability to correctly use.In the early game, you can use it to chase, you can use it when your duo is walking from base towards the lane to surprise the enemy, you can walk towards river and bring your jungler to an easy gank, you can use to scape ganks/all-ins ( Ashe can't kill you without Enchanted Crystal Arrow if you have E for example).

In late game you can use it to catch isolated enemies with a teammate, or it can be used as an overall pressure since the enemy team don't have any information. This ability is super flexible! how you use it will make a huge difference between a noob Senna and an experienced one.

General tips:

• This ability is a big part of why Senna is annoying to play against, you can hide your whole team before a teamfight so the enemy team can't engage on anyone.
• In the early game, you can trick the enemy botlane by walking to the sides while your duo walks towards them to engage. (HIGH COORDINATION REQUIRED)
• Control Wards reveal you. after leaving the ward's area, you will be revealed for an additional 1.75 seconds before camouflaging again
• If there is a Control Ward out of vision while in E, it will be revealed, so you can take it without risk.
• You can use this ability when warding to get that extra survivability and movement speed, since squishy champions struggle to ward without being in heavy danger.
• This ability is currently BUGGED (13.7 last seen): Seemingly random abilities can target you even when you're camouflaged. Instances that i have found: Katarina's Shunpo, Nami's Ebb and Flow, Zyra's plants, Aphelios' Onslaught.

R - Dawning shadow

Ability full description ACTIVE: Senna reveals herself before firing two global beams of spectral light in the target direction, granting sight of the area briefly along its path. The center beam deals physical damage to enemy champions hit. The broad beam shields Senna and allied champions hit for 3 seconds. The broad beam also collects any Mist Wraiths in the way.

When to use:

You want to use this ability in teamfights where you can hit the most amount of champions. It has a huge cooldown, so try to save it when close to important objectives.

Since it's global, you can also use it to snipe any enemy who got out with 1 HP. You need good coordination / high map awareness.

General tips:

• This ability DOES NOT DAMAGE ANYTHING BESIDE CHAMPIONS. Don't try to steal objectives.
• The shield scales with total number of mists.
• You can R + Flash. The ability will always shoot from the original cast position. Senna will face towards the same original direction, but if you time it perfectly, she will actually face towards the blink direction (similar to Ezreal's Trueshot Barrage + Flash combo). So use it to trick enemies (very situational)