Here's a a spoiler bit for the first 2 episodes, just to help everyone prepare...
Episode 1 – Rise of KnightMare.
KnightMare begins their plan in harvesting new energy for “the darknessâ€. Reaching into the mind of humans and feeding off their nightmares and fears. The old riders find themselves being needed once more but are unable to call upon the power. New faces arrive, to answer the call and become Earth's new hope of survival.
Episode 2 – A New Generation.
The new generation kicks into action as they go to work, all goes well until the power fades once more. The older generation find it within themselves that they much teach the new generation the true abilities of their new power. They go to seek out of other members of HJU, to see if they're still around to help teach the new generation. A new fight and a new journey begins.
I want to start the episode with lead riders from from each series and myself (Nami), as we will be the guides for the new generation. Everyone else in the HJU Alumni (secondary riders and extras), will be on standby in their worlds until we arrive. The first riders to awaken will be Decade, Kiva and Agito.
The nerf for Decade this time around is that, in able to transform and use the abilities of other riders, the other riders must awaken their powers. If Name A can't awaken Faiz... no Faiz for Decade.