The Participants (2015)

In an eerie, abandoned world where no adults are to be found, a gang of forgotten children plays games to gain the favour of Mikhail, the self-proclaimed leader of this strange and isolated society. Rebelling against Mikhail's tyrannical bullying, Emilia, Boris and the bird-like shaman boy Josef devise a plan to escape, twisting the rules to beat Mikhail at his own game.