Programming Language Used On The Game

My doubt here is about the programming language used to create the game.

I’m asking because I’m studying game programming and so far, I’m studying Lua.

When the main menu opens and when the credits appear, it is show to us that Lua is used on the creation of the game, but didn’t saw if they used another and didn’t find any information about this subject.

I know that C++ is important as well for games, but to know if something else was applied for this game, is helpful for me, to serve as a guide of what else I need to study, seeing that I enjoy games with lots of choices to make and Kevin Bruner has created several games with this theme, this information is very useful to me.