A magical cat from Bandle City, Yuumi was once the familiar of a Yordle enchantress named Norra. When Norra mysteriously disappeared, Yuumi became the Keeper of Norra's sentient Book of Thresholds. Longing for her master's affection, Yuumi seeks out companions to travel with, protecting them with shields of light and fierce determination. While Book tries to keep her on track, Yuumi is easily distracted by naps and fish. However, she always eventually returns to her quest to find her friend. In combat, she fires missiles that deal damage and slow the first target hit. She can gain a shield and increase her movement and attack speed. She can also channel a magical rite, launching five waves that damage enemies or heal allies. She can move while channeling. After being summoned by Ryze, she decided to travel with him. She looks like an ordinary cat but is capable of speech.

She meets Ryze on his journey and joins him since their goals align. Raised in the slums, Vi is a formidable woman—impulsive, hot-headed, and possessing very little respect for authority figures. Having spent much of her youth getting into trouble and serving time in prison, she is highly skilled in the art of survival. Though she once lived outside the law, she now uses her strength to maintain order. The Hextech Power Gauntlets she wears can punch through hardened criminals and reinforced walls with ease. In battle, she charges her gauntlets before dashing forward to deliver a powerful punch that deals damage and knockback. Her strikes shatter enemy armor to deal bonus damage and increase her attack speed. She can also unleash a shockwave with her next basic attack and generates a shield over time.

Jinx is a manic and impulsive criminal from the undercity. Haunted by the consequences of her past, she continues to bring about her own unique brand of chaos and destruction. Using an arsenal of powerful, self-made weapons, she triggers flashy explosions and rains down bullets, leaving mayhem in her wake. She serves as a symbol of rebellion, inspiring the downtrodden to rise up. She can swap between her weapons: 'Pow-Pow' (a minigun) and 'Fishbones' (a rocket launcher). Continuous fire with the minigun increases her attack speed, while the rocket launcher offers long range and area-of-effect damage at the cost of speed. She also fires a laser from her shock pistol to damage the first enemy hit and can toss out a row of three Flame Chompers. These grenades arm upon contact with an enemy to deal damage, or explode automatically after five seconds to damage nearby foes.