Jinx and Vi's sisters: Hex and Ivy
Lore: Hex and Ivy share a unique desire for controlled destruction. With both sisters, Jinx and Vi on opposite sides of the law, Hex and Ivy have plotted to get both of them together through calculated chaos and reconstruction. For them, there is no right or wrong, only an endgame: a vendetta, a blood feud against both of their elder sisters.
Jinx's constant dependence on adrenal stimulation and Vi's dedication to the force left both younger sisters neglected, alone, and forced to fend for themselves in the not-so-prosperous parts of Piltover. The city of Piltover believes that they exist in a state of good versus evil, while Hex and Ivy control what happens and when, so that they can exact their revenge. Together.
Passive - Hide and Seek: When Hex and Ivy are defeated in battle, only Ivy dies while Hex is granted a movement speed buff that decays over three seconds. If she survives long enough to perform a her resurrection spell uninterrupted, Ivy is revived at Hex's location. During this time, Hex has half of their combined max HP and can only perform basic attacks and her Q, which is changed to the resurrection spell. She cannot teleport back to base alone.
Q - Tag-team: Hex and Ivy switch out, changing the nature of basic attacks and skills (except for R). While Hex is in battle, she deals a ranged basic attack. While Ivy is in battle, her basic attack deals melee damage.
W - Cannonball (Hex)/ Vanish (Ivy): Cannonball: Ivy leaps into the air with Hex on her back and crushes a target location, dealing AoE magic damage. / Vanish: Hex and Ivy disappear and reappear to a target location. Upon reappearing, the duo receives an armor and magic resist buff.
E - Hurl (Hex) / Guardian (Ivy): Hurl: (Skill-shot) Ivy grabs Hex and hurls her at a target location. This skill applies on-hit effects and a slow that decays over two seconds. / Hex casts ethereal armor over Ivy for two seconds. The first attack or spell that targets Hex and Ivy is nullified.
R - Prepare for Battle (Passive): Hex channels a spell that charges from 0 to 50/75/100. The next basic attack or damaging spell dealt by Hex or Ivy applies however much true damage has been charged at the time. If Hex and Ivy are targeted by a basic attack or spell from an enemy champion, the spell resets to 0.