Board Thread:General Discussion/@comment-31283382-20131101162239/@comment-1387259-20131101170249

Hollows in general grow by feeding on souls and other Hollows. This process holds true from regular Hollow to Gillian, from Gillian to Adjuchas, and from Adjuchas to Vasto Lorde. A Vasto Lorde is far more powerful than the other forms, but is just as sentient as an Adjuchas, from what we know.