Totally neccesary info :>
Senna’s journey to become a Sentinel of Light started with darkness. It started with the Black Mist…

Senna first encountered the Mist at an early age, when wreckage from a distant Harrowing washed onto the shores of her home island. The Black Mist within the wreckage awakened upon contact with life. She and her village survived the ensuing storm of souls, thanks to the intervention of a nearby Sentinel… but in the wake of the attack, the Mist was still mysteriously drawn to Senna.

She was cursed, marked by the Mist so its horrors pursued her endlessly, the darkness drawn to her like dying moth to living flame. She could never know when it would strike next—but worse was when it didn’t come, and Senna had to imagine what awaited in every shadow.

The Sentinel who saved Senna, a brusque veteran named Urias, did not understand why the Mist was drawn to a solitary girl—but he knew if she was going to survive, she had to learn to fight back. And so, Senna joined Urias in the Sentinels of Light, a sacred order that could be traced back to the Blessed Isles, where the Black Mist originated. She proved to be a deadly enemy of darkness, mastering the relic-stone pistol Urias gave her, learning to channel her soul into light.

Yet even as Senna grew comfortable working with Urias, relying on him for gruff guidance, she learned to keep others at gun’s length. If she allowed them to get too close, they would only be hurt when the Mist came again. Senna could never stay in one place for long, something she and Urias learned when those who offered them shelter inevitably found themselves under siege. After even Urias was slain, Senna wasn’t sure if she could let anyone get close again.

Reluctantly, Senna sought out Urias’ family in Demacia, to tell them of his fate. There, she met his son, Lucian, who would not relent until Senna allowed him to join Urias’ parting vigil. From the very first moment she found herself flustered, wondering if her walls were enough to keep out someone so stubborn, full of humor and love. It became clear over time that Lucian’s place was with the Sentinels, as Senna’s partner, and Senna as his.

The more they served together, the deeper their bond became, and Senna realized that the value of her walls wasn’t what she kept out, but who she let in. Yet as Lucian’s love for Senna grew, so did his desire to save her from her curse. In time, it became his only focus, the light in his eyes passing into his gun—making Senna wary that Lucian would only see sorrow where there was love.

It was while researching a cure that Senna and Lucian came into conflict with the sadistic wraith Thresh. So close to answering mysteries about the Ruination and Senna’s curse, Lucian refused to turn back…

Thresh’s chains whipped toward Senna as she stood between the wraith and her husband. More painful than the scythe was seeing the look of anguish on Lucian’s face. With her last breath, Senna screamed for Lucian to run.

But as Senna felt the deathblow and knew she had lost, she realized there was a glimmer of hope. Her whole life, the Mist had haunted her—she didn’t need to fear it anymore. She could ride it into the darkness of Thresh’s lantern, and see what was inside.

Her curse had become her only chance for salvation.

While Lucian spent years seeking to grant his beloved peace, Senna explored her spectral prison. She learned that life had been the origin of her curse. Its spark shone brighter within her than in anyone else—she’d been infected with it when she first encountered the wreckage that brought the Harrowing. There, she’d been touched by a powerful, lingering soul, given its unnatural life…

It was life that the Black Mist could never let go.

She could use this force to pull the Mist into herself, empowering her to sever its hold over others in the lantern. Among the souls she freed were Sentinels who possessed lost knowledge of the Ruination’s origins, of her curse… and the love that created it.

When Lucian drove his broken pistol into the lantern, intending to end the torture of the souls within, Senna was waiting. She escaped, shrouded in Mist she’d drawn from other souls. She was dead, but also alive, thanks to her curse, wielding a relic-stone cannon that could channel darkness along with light, forged from the weapons of fallen Sentinels.

No longer running from the Mist, Senna now understands the suffering of the souls within. Though it is painful, she draws their Mist into herself, liberating them, and blasting darkness with darkness. Embracing her death every time she transforms into a wraith, she becomes like those she fought, only to be reborn again thanks to the life infecting her.

Though Senna and Lucian’s love survived even death, now they face the consequences of her rebirth. Senna knows what they have to do next, a secret gleaned within the lantern.

Find the Ruined King, and stop him at any cost…

INNATE - WEAKENED SOUL: Senna's basic attacks On-hit icon.png 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 and deal bonus physical damage equal to 1% − 10% (based on level) of target's current health, rendering the target immune to further Mist applications for a few seconds. This damage applies Life steal icon.png 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.

Champions and large monsters will spawn a Mist Wraith.
Epic monsters will spawn 2 Mist Wraiths.
Minion 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 Attack damage 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.

Piercing Darkness
COST: 70 / 80 / 90 / 100 / 110 MANA
COOLDOWN: 15
CAST TIME: 0.4-0.25
TARGET RANGE: 600 - 1100
RANGE: 1300
WIDTH: 100 / 280
ACTIVE: Senna fires a spectral laser in the direction of the target unit,healing herself and allied champions hit, and dealing physical damage to enemies hit in a thinner line. Enemies hit are slowed by 15% (+ 10% per 100 bonus AD) (+ 6% per 100 AP) for a duration. The damage against champions applies life steal at 100% effectiveness.

HEALING:
40 / 55 / 70 / 85 / 100 (+ 30% bonus AD) (+ 40% AP) (+ 1.6 per 1 Lethality)
PHYSICAL DAMAGE:
30 / 65 / 100 / 135 / 170 (+ 50% bonus AD)
SLOW DURATION:
1 / 1.25 / 1.5 / 1.75 / 2
Upon being hit, 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.

Piercing Darkness' current cooldown is reduced by 1 second on-hit.

Last Embrace
COST: 50 / 55 / 60 / 65 / 70 MANA
COOLDOWN: 11
CAST TIME: 0.25
TARGET RANGE: 1300
EFFECT RADIUS: 280
WIDTH: 140
SPEED: 1200

ACTIVE: Senna throws a globule of Black Mist in the target direction that deals physical damage to the first enemy hit and attaches to them for 1 second.

PHYSICAL DAMAGE:
70 / 115 / 160 / 205 / 250 (+ 70% bonus AD)
After the duration or when the target dies, the Black Mist spreads out of the target, rooting them and surrounding enemies for a few seconds.

ROOT DURATION:
1 / 1.25 / 1.5 / 1.75 / 2

Curse of the Black Mist
COST: 70 MANA
COOLDOWN: 26 / 24.5 / 23 / 21.5 / 20
CAST TIME: 1
EFFECT RADIUS: 400
DETECTION RADIUS: 400

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 without performing actions that break stealth.

EFFECT DURATION:
6 / 6.5 / 7 / 7.5 / 8
Allied champions who enter the mist gain Wraith Form for a duration equal to the remaining duration.


WRAITH FORM: Gain Ambush. Enemies will have obscured vision of camouflaged Wraiths moving outside of the mist. Wraith Form can be regained if lost by breaking the camouflage after 1.75 seconds without 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% (+ 5% per 100 AP) bonus movement speed.

"Shadows catch the fallen."

Dawning Shadow
COST: 100 MANA
COOLDOWN: 160 / 140 / 120
CAST TIME: 1
TARGET RANGE: GLOBAL
WIDTH: 320 / 2400
SPEED: 20000
ACTIVE: Senna fires two waves of spectral light in the target direction, granting sight of the area briefly along the path. The center wave deals physical damage to enemy champions hit and reveals them for 3 seconds. It also collects Mist Wraiths it hits.

PHYSICAL DAMAGE:
250 / 375 / 500 (+ 100% bonus AD) (+ 70% AP)
The broad wave grants a Hybrid resistances shield to Senna and allied champions hit for 3 seconds.