A former student of Beacon Academy and the main protagonist of RWBY. Ruby's weapon of choice is her High-Caliber Sniper-Scythe known as Crescent Rose.
Ruby first appeared in the "Red" Trailer visiting the grave of her mother, Summer Rose. After an invitation from Headmaster Ozpin following a short battle with Roman Torchwick, Ruby attends Beacon Academy in order to become a Huntress. During her time at Beacon, she becomes the leader of Team RWBY, consisting of Weiss Schnee, Blake Belladonna and her older half-sister, Yang Xiao Long.
Ruby is self-admittedly obsessed when it comes to weapons, which shows in her complex design and craftsmanship of Crescent Rose, her High-Caliber Sniper-Scythe which she designed herself at Signal, as well as her eye for detail when observing other people's weapons and tools.
This weapon can transform between a scythe and a sniper rifle and can fire Dust rounds in either form with massive force, as demonstrated in the "Red" Trailer when she used a Gravity Dust magazine. Rather than compensate for it, Ruby harnesses the recoil to enhance her mobility in combat, firing shots to propel herself short distances, simultaneously attacking and evading an opponent. It is also capable of using Fire and Lightning Dust.
Ozpin has noted upon meeting Ruby that he has only ever seen one other scythe wielder as skilled with such a dangerous weapon; that person is none other than Qrow, who turns out to be Ruby's teacher and uncle. According to Ruby, prior to learning under Qrow she was "complete garbage", although it is unclear if that only applies to her scythe skills.
Despite showing a preference for engaging enemies in close combat, Ruby does possess enough accuracy to land headshots against Grimm, but notably needs to stand still to do so consistently, usually by anchoring her scythe to the ground to act as a monopod.
Crescent Rose's blade can also bend back slightly, though this is only shown when Ruby rushes forward, and the tip of the scythe hits something.
Ruby's Semblance allows her to dash with an unnatural speed in whatever direction she chooses at the cost of Aura. This happens so fast she sometimes gives off the illusion of teleporting.
She has displayed the ability to use this Semblance midair, as well as to create powerful whirlwinds that can suck in and knock away objects and foes caught by it.
She displayed much greater control over her Semblance, using it to repeatedly change directions in mid-air and attack at high speed. She also exhibited the ability to seemingly dematerialize into three separate clusters of petals which then flowed around an opponent before reforming. The exact mechanics of this ability are not yet clear.
She also increases her ability to pick up and carry someone, as her joint attack with Nora Valkyrie on the Geist was a vast improvement over the time she carried Penny Polendina. Another amped ability is her encircling of air, which she previously used successfully against Team JNPR and unsuccessfully against Mercury Black. Previously it was smaller, but she is now capable of enveloping her enemy in a tornado-like rush of air.
Notably, whenever she uses this Semblance, she leaves a trail of rose petals in her wake that dissipate over time. It is unknown what causes this, but these rose petals are not merely symbolic and can be perceived by others. Weiss once waved her hands to brush them away, and Ozpin comments on witnesses who reported rose petals left behind in a dance club.