true ending

noun1

1. •
   An ending in a video game that leaves no ambiguity, mystery or doubt. It usually requires a particular playstyle or choices throughout or sometimes even an extra playthrough. This leads to a connotation of it being difficult to achieve.

   • The true ending proved to be quite difficult for most people to obtain. If you really get stuck on the puzzles and don’t rely on guides, you might take well over a dozen hours to finish the game. — 2013