Toei uploads the Main Trailer of Saber + Zenkaiger: Superhero Senki today featuring the mysterious character played by Fuku Suzuki.
In this trailer, it was revealed that Sword of Logos has a third base called Agastia Base which is a Forbidden Land. The base holds the books of Super Sentai & Kamen Riders. The main villain of the movie - Asmodeus breaks free the Forbidden Book from this base which will shake the world.
It causes the story world to fuse with the real world causing chaos. This leads to Kamen Rider Saber characters ending up in Zenkaiger World and Zenkaigers in Kamen Rider Saber World. Asmodeus also creates two monsters in the film who look as if they are the Megid & Warudo counterparts of Zenkaizer & Kamen Rider Saber respectively. (Let's call them Zenkaizer Megid & Saber Warudo for now till the official announcement of their names).
Touma & Kaito meets the mysterious boy who is the Key to the story. They exchange talks and team up to restore the world.
In their fight to restore the world, they meet with Legend Heroes like Imagins who turn out to be Guardians of Time - Kamen Rider Den-O, 'Devil who Stands on the Top' - Kamen Rider Zi-O (in his Grand Zi-O form), 'Young Next Generation CEO Hero' - Kamen Rider Zero-One, Legendary Samurai - Doggie Krugger the Deka Master.
They also get help from other Legend Sentais like Shinken Green, Kiramai Blue, Washi Pink & Ryu Commander.
Kamen Rider Kenzan who is a Ninja Rider will team up with Kakuranger's Ninja Red to fight against the Combat-men.
In the end, Kamen Rider 1 (Old) and Akarenger stand together to fight against all the enemies in the movie.