Forestize is the event where the Shinju-Sama deploys the heroes for battle in an alternate layer of reality.
First, the heroes get a message on their phone that warns them of the event, with a small text reading "Vertex approaching. Deploy to protect humanity.". Time then stops for a moment, save for the chosen heroes, and a rainbow-colored light envelops the land. Rainbow water spills over the hills (or the ending of the barrier) and a bright light ensues. The heroes then find themselves in the dimension where the Shinju-Sama resides.