[@Cenco]

Well if it is "unknown" that would be kinda odd imo. I think that being a color would make more sense, but hey that might just be me. The only transformation abilities in canon belong to red avatars, which is a bit odd imo and again never really explained as to why, but at the same time considering the ability's versatility it could also be justified as almost any color imo. I'd still say that it is likely more of a red, or possibly white/black ability [the latter of which is very ill defined].