Thanks to a new article entitled "Whatever Happened to Toasty?" on 2K's Cult of Rapture website, we now know more about the subtle changes being made to one particular splicer in BioShock 2.
For BioShock 2, the team worked with the original model and envisioned what the passing years would do to his body, scavenging for ADAM to keep up his habit. The result was an older, more broken down Toasty that had taken quite a beating in the looks department. Four pieces of concept art are also included.
The process to create the new Toasty is very iterative. To start, the team sits down and looks at the original character and brainstorms where they would like to go with that look. Then, they draft a series of sketches showing a wide array of possible design decisions. The sketches included here show only one of many passes at Toasty's head and body.
Sketches created, the team then sits down and picks and chooses from all the options what they like best -- a tumor here, a pant leg there -- and with those likes and dislikes, they repeat the process until the end product: A final sketch of a new, older Toasty.