Kamen Rider Hirogo: Series

Sequel to Big Hero 6/Venom (Movie)/Hirogo
After the events of Riot, Drake, and Callaghan, the group is on a break. However, their journey of villains won't end there. More importantly, a mysterious man who calls himself "Dark Kabuto" is interfering with Big Hero 6's fight against those villains. WHAT is the real identity of the dark warrior?
(Warning: THIS WILL BE A LONG FANFIC, SO BUCKLE UP!)