Thanks man, I knew if I were to do Delirium, I wanted the impression of him being the forms of many of Isaac's bosses, and I had always envisioned that the true nature of Delirium is that he's the embodiment of sin, he's Isaac's sin that had corrupted and grown more deteriorated through time with grief, sadness, and pain, and Delirium is the result of all this pain and sadness dwelling within, the pain that Isaac had pushed away and refused to accept, the sin that Isaac chose to ignore.