Growth is a power.
Growth is best described simply as an increase of body size. There are multiple ways one can achieve this, however. Obviously, there is the natural assimilation of organic compounds that most fleshy organisms and Rahi undergo, but that is not considered an example of this power.
Growth outside normal means would be considered an example of this power. Ways of achieving an increase in body size include a simple application of an ethereal aura, like that contained in a Mask of Growth, energy absorption, or bodily expansion. The last one being true growth is debatable, since growth usually entails a mass increase instead of just a density relaxation.
A common question is where the extra mass comes from, since, according to the First Law of Thermodynamics, mass cannot be created or truly destroyed. There are four possible explanations for instances of Growth power where a cause is not specifically cited.
- A common explanation (particularly in comic books) is extradimensional mass redistribution. The theory is that a kind of subspace is opened, in which there is an atmosphere of sorts. This atmosphere obviously does not contain the component atoms of one's body, but part of the growth process rearranges the subatomic particles in what matter is there. This effectively transmutes the subspace's matter into bodily molecules, which are then assimilated appropriately by the Growth user.
- Another explanation is the transmutation of molecules from the immediate environment. This would cause a puff of smoke-like vapor as the atmosphere around the being is turned into body mass, and the rest of the atmosphere rushes in to fill the resulting vacuum.
- A third is an energy-mass conversion, using energy from the environment. This is used less often than the others, since there are a couple problems. The first issue is that the amount of energy needed to transform into matter would be so huge the growth process would be painfully slow. The second issue is returning to normal size. The mass being converted back to energy would be released in an enormous discharge, possibly laying waste to a huge area around the Growth user. For villains, this may not be a moral issue, at least. Overall, this theory is the least efficient and most flawed.
- A fourth, and somewhat unusual, explanation is a shift in the fabric of reality, in which one of the basic concepts of reality is thrown out of sync, but only around the user. In this case, the concept being altered is Scale, and the alteration causes a positive shift in the concept of Scale which only affects the user, causing an increase in size in relation to the rest of the universe, which is shifted back to normal when the power is deactivated. This is most likely how the Mask of Growth works.
Regardless of its source, Growth is a power that causes a positive change in the size of the being or object using it, usually, but not always, accompanied by a similar change in mass.