After a few days of observation over both her body and state of mind by various medical professionals that were familiar with Clayface, it was decided that Annie was, for all intents and purposes, a young girl in body and mind, and that Matt Hagen no longer existed after being absorbed into her.

Annie was soon approached by Bruce Wayne, who told her that he had heard about her and that she had nowhere to go once the time came for her to be released from her examinations. As a way to help acclimate her into society, he offered her a place to stay at Wayne Manor. As Batman, his reasons for this were, of course, to help a child who had nowhere else to go, and to be able to monitor her closely.

Bruce had meant to keep Annie in the dark about his secret until he deemed it the proper time, but the young shapeshifter had managed to realize quickly that Tim Drake was actually Robin. This left Bruce both annoyed at the truth being revealed so quickly, and impressed by the girl’s quick realizations.

Annie had an aversion to the idea of using ‘Clay’ in any part of her name, as the thought of being associated to Clayface in any way wasn’t something she was keen on. One day, upon managing to try some crayfish for the first time, Annie learned that another word for the creature was ‘mudbug’, and she actually thought it sounded cute.

And so Annie decided that the name she would adopt as a hero would be the Marvelous Mudbug.

Marvelous Mudbug’s costume is formed out of Annie’s own slime. Such were the perks of being a shapeshifting being made of slime, allowing one to create any kind of outfit they wanted. However, even though Annie could do this, she still loved the idea of shopping for clothing and trying on actual clothes.