Season 4 (Protectors of the Planets)

The fourth and final series of Protectors of the Planets premiered on April 10, 2016 on JBUC and concluded on June 12th 2016. The series consisted of 7 episodes altogether; however with longer episode lengths with an hour.

Synopsis
As with the preceding three seasons, Series 4 incorporated several ongoing story arcs which were resolved in the finale episodes. In Series 4 these threads included: Finding River Song and The Mystery Man, The Wombat King and The Bear King's attempts to return to their original world and the original being of the universe forcing the Defteros and Prota to collide.

Chronos is revealed to by The Mystery Man in the season finale, due to The Mystery Man also being transported to the Defteros between Season 14 of Wombat and Bear and Infinite Protectors. Over thousands of years, he became insane and gained the persona 'Chronos'. Wanting to go back to Prota he tried to force the universes colliding thus transporting people's souls first however it did not have enough energy. However in the finale it did work, resulting in both universes shutting down. The only way to solve the issue; move everything into a new universe, costing a powerful soul. River Song sacrifices herself just in time before both universes had completely collapsed.