Just thought what also might make an awesome "period" horror-sandbox. Dr. Jekyll and Mr. Hyde, maybe call it simply something like Hyde. The same classic story set in victorian london but with a twist, as Jekyll tries to perfect his formula during the day come night he transforms into his Hyde persona. A Jekyll you source and experiment with different combinations of chemicals which is a mini-game, also you try and cover up the tracks of Hydes activities from the previous night. Depending on the formula and your actions/good or bad you mutate into different forms of the Hyde persona. Preventing crime, saving innnocent lives or commiting crime and preying on the innocent. Become an urban myth and vigilante or a horrific montrous villian the choice is yours.