Summary
Aura is the manifestation of one's soul and is stated to be energy of living souls in RWBY and can be used for a wide range of abilities. The specific abilities and their strengths differ from individual to individual and are dependent on a number of factors, such as experience, training and innate skill. It is predominantly used for passive protection from harm. Some people develop an active power called a Semblance. It can also be used to manipulation Dust.
Aura
Aura is an ability that all those with a soul can use, at least with enough practice. Because Aura is the manifestation of the soul, it can appear very differently depending on who is using it. For example, the color of Aura differs from person to person: Ruby Rose's is red, Jaune Arc's is white and Yang Xiao Long's is yellow, among many others.
It is mentioned that anything with a soul has an Aura, including Humans, Faunus, and animals like Zwei; even synthetic people with souls, such as Penny Polendina, can generate an Aura. The Creatures of Grimm, being soulless, are the only known form of life that does not have Aura.
Skilled users of Aura can create their own barriers or even increase their own abilities in some way. Weapons and armor can also act as a conduit for Aura, allowing for an even wider range of offensive and defensive capabilities. This even applies to nontraditional "weapons", such as a loaf of bread or a leek, as seen during the food fight in "Best Day Ever".
It has been shown that the strength of an Aura degrades with continual use. This limits the applications of Aura in combat as, with time or heavy use, a person's Aura will decay to the point where they are left weakened or even incapacitated. Aura being completely depleted is visually represented as a colored sheen glowing along the length of a person's body or with colored particles flying off the body, indicating that they can now be physically injured. Aura flickering means it is close to being depleted.
Similarly, one's Aura regeneration rate is dependent on the individual, varying per person.
The powers of a Maiden are said to be tied to Aura, until the death of the individual, which causes the power to separate from their Aura.
While those using robotic prostheses such as Yang Xiao Long and James Ironwood are apparently able to shield their artificial anatomy with Aura, those who use Grimm transplants are not such as Cinder Fall, due to their aforementioned soulless nature.
It is stated to be directly linked to the users soul.
So it is implied that it uses limited Soul Manipulation to manifest the aura into life energy.
Semblance
Semblance is a power exhibited by certain characters in RWBY. It is developed from a person's Aura.
According to "Aura", the fourth installment of RWBY: World of Remnant, a Semblance is a more tangible projection of one's Aura. Pyrrha Nikos implied this connection when she told Jaune Arc that the use of Aura can help him to discover his Semblance. Miles Luna refers to Semblance being "fueled" by Aura. A user should be unable to use their Semblance once their Aura has been depleted.
Those that use Semblance are able to manipulate certain physical phenomena according to the nature of their power. Some individuals, such as Weiss Schnee, are able to use their Semblance to create "glyphs" that generate some desired effect - the most prominent being sudden disruptions in movement and bursts of momentum. Ruby Rose is able to move at incredible speeds, while Pyrrha Nikos was able to manipulate magnetic forces. Some have Semblances that depend on external factors, such as Nora Valkyrie's ability to convert electricity in the environment into physical strength.
Using Dust, certain individuals can modify their Semblances with elements, such as Weiss using Myrtenaster to change her glyphs and Blake inserting Dust vials into Gambol Shroud to give Shadow clones elemental properties.
According to Winter Schnee, Semblances are like muscles and are able to grow and evolve. A clear example is her younger sister's eventual mastery of summoning.
Some semblances can go even deeper connection to Aura such as Yang Xiao Long whos very depend on her Aura as it taking damage powers her semblance which in turn will put her into a Burn state that increase all of her physical attributes.
Dust
Dust is a source of energy in Remnant. The physical properties of Dust make it incredibly useful for a variety of purposes, particularly in the weapons of many characters in the series. It is known to make a distinctive "shimmering" sound passively and when in use. The name "Dust" is implied to be a reference to the primordial state which mankind was born from. As a natural resource, it is sometimes poetically referred to as "Nature's Wrath", or more prosaically as an energy propellant. For more information the "Dust" the first installment of RWBY: World of Remnant.
As an energy source, Dust can be triggered by the Aura of Humans and Faunus, as well as combined with their semblances to give them new properties. Dust can be found in two distinct states, crystalline and powdered. Dust, whether crystalline or powdered, is highly explosive. For example, during the Dust store robbery, Roman Torchwick threw a crystal at Ruby Rose's feet and fired at it, causing a sizable explosion. The powdered form appears more volatile since something as innocuous as a sneeze is enough to detonate a cloud of Dust.
Types of Dust
- Heat Dust: It can be turned to a fiery projectile when superheated, that splatters to the ground when blocked, to make weapons out of obsidian or some other form of black glass and to melt ice by generating heat.
- Combustion Dust: It is used to power Yang Xiao Long's sports motorcycle, Bumblebee.
- Electricity Dust: can be used to generate electricity in forms such as bolts of lightning, electrical currents and can be used to stun enemies.
- Fire Dust: can be used to create fire in various forms, such as fireballs and fire waves.
- Steam Dust: can generate clouds of steam and is created by combining Fire Dust with Water Dust.
- Gravity Dust: can be used to manipulate gravitational fields, often to pull objects or create a field that pushes outward.
- Hard-Light Dust: can be used to form solid objects made of light energy.
- Ice Dust: can be used to create ice in any shape, such as crystals, thin sheets or even large structures like curved ramps or platforms that float in water and is formed by the combination of Water and Air Dust.
- Plant Dust: still has yet to be used or even appear in the show proper.
- Rock Dust: can be used to create rocks.
- Water Dust: can be used to create water.
- Wind Dust: can be used to create wind in various forms, such as gusts and tornadoes.
Possible Uses
Aura
- Creating a passive Aura around oneself
- Creating Barriers
- Strengthening the users attacks
- Empowerment to characters who have yet to awaken their Aura
- Powering the users Semblance
Semblance
- Can vary depending on the character
- Absorption
- Fire Manipulation
- Glyph Creation
- Duplication
- Matter Manipulation
Dust
- The wielder can gain Elemental Manipulation
- Create fireballs
- The ability to create barriers
- Can empower themselves
Possible Limitations
Aura
- If the aura is broken the users is left extremely vulnerable
- Aura has set amounts of damage it can take which will vary from person to person
- While their aura is broken they're unable to use their Semblance
Semblance
- Over using their Semblance will deplete their Aura
Dust
- If the users is unable to use it correctly it will backfire on the users
Notable Dust Users
- Ruby Rose uses dust bullets that vary in elements.
- Weiss Schnee uses dust with her weapon to change the effects of her Semblance, giving them varies new effects such as fire balls, ice and time manipulation.
- Hazel Rainart will infuse them directly into his arms giving him electricity increasing his strength.
- Raven Branwen has dust infused blades that have different effects depending on the blade.