On Arrow Season 4 Episode 20, the conflict between John and Andy comes to an end while Oliver finds the light to fight Darhk's magic.
It's the beginning of the end for Team Arrow. At least as far as this season goes.
Arrow Season 4 Episode 20 starts the march towards the ultimate showdown between Damien Darhk and Team Arrow. Death and fear versus light and hope. But first, the playing field needed to be cleaned up a little.