Size Alteration

Sometimes confused with "elasticity", Size Alteration is a term used to describe the ability of some characters to increase or decrease the volume and mass of organic and inorganic matter. In many cases, people who possess this power can only use it to affect their own physical person, however this is not an absolute, and there have been many circumstances where individuals have developed the ability to alter the size of other people or objects.
Usually, the mass and density of the affected item will increase or decrease in proportion to the volume of the item in question, but this too is not always a constant.