Tessa, the Matriarch of Balance
Preface (skip this if you want, just an intro): Tessa is something I have been cooking for a while. After reading 
's new lore, I got interested in him on a story-based level. I took what I read and started make my own stories that could fit in with him and progress his story, and the story of Ionia and Noxus. I will share brief details in this post about her background and such, but a lore will be added later. Also, do not be harsh. I am a person and will talk my ideas through will you guys if you are civil. Any disrespectful and or rude comments will be ignored. You can still be constructive while being negative. Thanks!
(Edit: Had to fix divider links)
Table of Contents (the divider start and end each section)
Basics Abilities & Thoughts on Abilities (dividers will divide each ability into their own section) Scalings per level Artwork & Credits to Artist To Do Skin Ideas
Basics:
Sex/Gender - Female
Lane: Mid
Class: Mage (Combo / Burst)
Faction: Ionia
Ally/Allies:
Enemies: 
Abilities:
Passive: Lumen and Umbral Tessa wields two powerful weapons, the Umbral Staff and the Orb of Lumen, each imbued with their own magical power. Tessa's spells and their effects are changed based on the last spell cast.
Lumen Spells - Change Tessa's alignment to Light. Umbral Spells - Change Tessa's alignment to Shadow.
(The first spell Tessa levels up with give her that spell's alignment first. Her E cannot be taken first.)
Q - The Orb of Lumen Cooldown - 10/9/8/7/6 seconds / Mana Cost - 40/45/50/55/60 / Range 1350
Tessa launches a flurry of light attacks from the Orb of Lumen that deal 50/80/110/140/170 (+25% AP) magic damage per light attack, subsequent attacks deal 33% damage. If a light attack damages an enemy champion or kills a unit, it explodes dealing 40/75/110/145/180 (+25% AP) magic damage, subsequent explosions deal 33% damage. Light attacks cannot pass through enemies. Light attacks always deal full damage to lane minions. Changes Tessa's alignment to Light.
Passive - Lumen and Umbral
If Tessa is Light aligned: The Orb of Lumen will be cast as well dealing true damage and can NOT pass through enemies. The Orb of Lumen will deal full strength even if enemies have been hit by subsequent attacks. The Orb of Lumen will be destroyed upon hitting an enemy unit but has an increased blast radius if it hits an enemy champion or kills an enemy unit. The Orb of Lumen is cast after the initial light attacks.
If Tessa is Shadow aligned: The Orb of Lumen will be cast as well dealing magic damage and can pass through enemies but dissipates if it does not continuously hit enemy champions. The Orb of Lumen will not deal full strength if enemies have been hit by subsequent attacks. The Orb of Lumen will not be destroyed upon hitting enemy champions. The Orb of Lumen is cast after the initial light attacks.
W - The Umbral Staff
Cooldown - 14/13/12/11/10 / Mana - 60/65/70/75/80 / Cast Range: 850 / Effect Range: ? (Similar to 
's W).
Tessa slams her staff to the ground and summons a ring of shadows over a targeted location. Shadows take 1.25 seconds to form. Once formed, they collapse inwards dragging and deal 60/100/140/180/220 (55% AP) magic damage to enemies captured. Changes Tessa's alignment to Shadow.
Passive - Lumen and Umbral
If Tessa is Light aligned: The shadows will charm the enemies hit for .5/.75/1/1.25/1.5 seconds.
If Tessa is Shadow aligned: The shadows will cause the targets to flee in random directions for 1/1/1.5/1.5/2 seconds.
E - A Change of Fate Cooldown - 20/18/16/14/12 seconds / Mana: 80 all levels / Range: 1 (self)
Tessa switches her magical energy to the opposite form (Light to Dark; Dark to Light).
Passive - Lumen and Umbral (Takes form changed from)
If Tessa is Light aligned: The Orb of Lumen is taken off cooldown. If Tessa is Shadow aligned: The Umbral Staff's current cooldown is reduced by 50%. (Only applicable if either of these spells are on cooldown)
R: Statera Cooldown: 120/90/60 seconds / Mana - 75 per part / Cast Range P1 - 1000 / Effect Range P1 - (slightly bigger than MF E) / Cast Range P2 - 1 (fires from self) / Effect Range P2 - 750
(P1) Tessa unleashes the Orb of Lumen's light to create a glimmering orb that hovers over a targeted area. After 3 seconds, the Orb of Lumen's true essence denotates dealing 200/300/400 (+40% AP) magic damage to all enemies with the Orb's radius. This cannot be detonated early. P1 - Changes Tessa to Light.
(P2) 1 second after casting part 1, Tessa gains the ability to slash with the Umbral Staff. Upon doing so, Tessa knocks back enemies in a cone and deals 100/150/200 (+40% AP) magic damage to all enemies hit. P2 - Changes Tessa to Shadow.
Ability Notes: (Just why I did what I did)
I wanted a champion that had the theme of balancing two different aspects of duality and would fit in with Ionia. Thus, I decided to do something related to Yi and Yang. Popular references of this were Light and Dark, so I decided to base her off of that... and she fits in with the idea of her being a part of the Order of Shadow so it all worked out.
I wanted the Light and Shadow part of her passive to be the main part of her kit, thus I created the two weapons. Using her abilities in different ways allows Tessa to create endless combos during fights. A true master of Tessa would be deadly.
Two of her abilities were meant to relate to her weapons. Thus her Q is her Orb, and her W is her staff. Her E is meant to be used as a form of showing that she does control Light and Dark, and it isn't the weapons that are giving her the strength. Tessa in her lore is that she controls all of duality, but in game she only controls light and shadow. Also, her staff and orb control all of duality. The Orb controls things like Light, Love, etc. while the Staff controls the other half of duality (Shadow, Hate, etc.). This is also why the shadows from her W can charm or fear enemies.
Her ult was meant to be more lore-based than anything else. She meant to be able to control them and bring them into balance with each other. The Orb does nothing really with the knockback from the staff because enemies can just walk out of the Orb's radius and be save. It requires Tessa to land the shadows from her W and/or the second half of her ult. If she fails to unite the two ends, she loses some nice damage.
I am willing to answer other questions you have in the comments! ^.^
Scalings per level:
Health - 600 (+75 per level) Health Regen. 5.5 (+0.55 per level) Attack Damage: 54 (+4 per level) Attack Speed: .625 (+1.25% per level) Armor: 25 (3.6 per level) Magic Resist: 25 (+0.75 per level) Movement Speed: 330 (+0 per level)
Stats and scalings were taken and randomized from the league of legends fandom wiki with the champions 
and 
used as my data pool.
Artwork and Credits to Artist:
Credits: Chrix Design
To Do: Add Lore.
Skin ideas:
Very raw ideas
Release skin - Sweetheart
Tessa's light theme could be love. Tessa's dark theme could be hate.
Other ideas right off the bat:
Life & Death
