Jinx is a new AD carry who channels Harley Quinn, and uses a rocket-launcher and a minigun.
Keen-eyed League of Legends fans may have noticed an odd blog post on the official League of Legends website earlier in the week, that featured a vandalized version of Vi's champion spotlight. Riot has now revealed this to be the work of the League's newest champion: Jinx, The Loose Cannon. Jinx has a very "Harley Quinn" vibe going on, and is a new ranged AD carry who uses a rocket launcher and a minigun.
"Jinx is a versatile marksman armed with an arsenal of eclectic weapons. Her assortment of arms wreaks a ton of havoc, enabling her to deal brutal bouts of damage at the expense of mobility. One of the most important facets to playing Jinx is harnessing the power of Switcheroo! to safely harass her enemies from a distance with her rocket launcher before unleashing a hail of minigun pain when the moment calls."
Jinx hails from Piltover, the same town as previously released champions Caitlyn and Vi, and has somewhat of a rivalry with them. Jinx's weakness is that she has no real escapes in her arsenal, so she will have to rely on proper positioning a lot more than other AD carries. Her ultimate, "Super Mega Death Rocket!" brings another "global" ult to the game, working very similarly to Ashe's crystalline arrow.
Riot previously teased a new storm dragon champion, but specifically stated that he would not be the next champion to be added to the game. As of now, there's no word from Riot on when we can expect to see Jinx in-game.
Source: League of Legends.