Cosmic Dragons get larger as they become more experienced. Brand new cosmic dragons, called hatchlings, usually start quite small comparatively. Ria, having ascended by outgrowing her universe, is naturally very large for her experience level. A fact that was hidden by her not having the knowledge most hatchlings have from the start. At the time of this comic, she had pretty much caught up to the other hatchlings in skill, but to Kxaetl and the other hatchlings, it just appeared that she had simply grown incredibly fast.