New champion!

Camille's passive ability is Adaptive Defenses, which is exactly what makes her great at duels. When she uses a basic attack on a champion, she gets a shield that protects her against that champion's primary damage type. The shield's strength scales with her maximum HP, making her a very formidable opponent in a 1v1 situation.

Her Q ability is called Precision Protocol, which makes her next basic attack do bonus physical damage and gives her increased movement speed for a short time. If you cast Precision Protocol again quickly before attacking, Camille gets an additional strike. If she continues to wait after recasting her Q ability, the second strike will do extra damage, partially in true damage.
Camille's W ability is Tactical Sweep, which sends out a cone of damage to all enemies inside it. If enemies are in the outer half of the cone, they will be slowed, take extra damage based on their maximum HP and heal Camille.
Hookshot is Camille's E ability, which predictably fires off a directed hookshot. If the hook hits a wall, she'll be pulled to it and then be able to hit E again to cast Wall Dive. Wall Dive allows Camille to dash in a chosen direction, and if she hits an enemy champion she will stun all enemies in the surrounding area, increase her range and gain bonus attack speed.
Camille's R ability is Hextech Ultimatum. With Hextech Ultimatum, Camille jumps onto the targeted enemy champion and locks them into a hexagon, allowing her to deal with them 1v1 while other enemies are locked out of the zone. While in the Ultimatum, Camille does bonus magic damage. It goes away after a brief time or is canceled if Camille leaves the hexagon.