I mean like if you finish all levels, when on every door it says completed a portal will come from the bottom to the top and when you go through it you are getting to a place. Also there are secrets in every game and in one level the green one there is two. I want to make a series out of my games and want the characters meet eachother. This game is a spin off and you get like sorta side news to the series.
And I didn't know that, but like every professional game dev do I am gonna call it a feature and not a bug.