In Kamen Rider Ghost: Truth! Secret of Great man's Eyecon, Saionji will revive da Vinci Gamma and that's not all. Just look at Saionji's Left Hand. It looks like his hand has turned into a Robotic Hand or probably using an Attachment.
Takeru's 19th Birthday will be celebrated in Kamen Rider Ghost: Truth! Secret of Great man's Eyecon! and between Takeru & Akari you will see a Young Boy. The identity of this Boy is not known yet.
Takeru & others will travel (along with packed bags) to Gamma World to meet Alain and others.
In Kamen Rider Ghost: Truth! Secret of Great man's Eyecon! we will get to know about the truth behind the Birth of Gamma (not Gamma World) and the Past of Saionji and Takeru's Father.