Coming from independent developer Toby Fox, Undertale became one of 2015's surprise success stories and one of the most acclaimed games of that year, with Fox having released some early concepts, ideas, and more from the game's beginning stages.On Twitter, Undertale developer and creator Toby Fox share numerous images of from an old notebook, which revealed numerous concepts, sketches, and more from Undertale before the game came to fruition. While the game surely changed dramatically from its original state in Fox's sketches and notes, it's still a fascinating look into game development and the beginnings of a game that, since its release, has been beloved by many.Undertale originally released in 2015 for and drew critical acclaim and a passionate fanbase since release, with the title drawing numerous comparisons to games such as Earthbound and other quirky RPGs from the 16-bit era. The creation of Undertale was done almost entirely by developer Toby Fox, who designed the title, created its art, and composed its score, with other artists also helping to contribute on some of the in-game art. Most of all, Fox concludes with an important message for aspiring game developers that "you don't have to draw amazingly to make a game", along with the advice that you also "don't give a skeleton a fedora."Undertale is available now for PC, Mac, and Linux - you can check out some of Fox's sketches, concepts, and notes on the game's development below: