That's true, that might be a bit unfair haha.
Regarding the engine, I used SDL2 which is a library or a set of libraries, not an engine. So I guess we can say that the "engine" is made by me for this particular game with the help of SDL2.
Wow, a self made "engine", we don't see a lot of those around... O.o
Haha I just like having control over everything what happens in my game. But it's easier than it sounds really, at least for simple 2D games :)
