(In Planeptune, a young blue haired boy is seen in a gaming room playing "Sonic Generations".)

https://youtu.be/hGobge1kfjo

(The boy got excited about getting the "A" rank.)

????: WHOOOOOOOOO! Yeeeeeeah baby!

(Suddenly he feels a buzz, and looks at his watch, detecting a bugster attack. Then he goes to his shelf, where he sees his Gamer Driver and a gashat.)

(He places the driver on his waist before activating his gashat.)

MIGHTY ACTION X!

(Then he prepares to transform.)

????: Henshin!

GASHAT! LET'S GAME! METCHA GAME! MUTCHA GAME! WHAT'S YOUR NAME? I'M A KAMEN RIDER!

(The boy becomes Kamen Rider Ex-Aid.)

Ex-Aid: I'll clear this game with No Continues.

(Meanwhile in a valley, some bugsters are seen attacking the villagers as they infect them. Suddenly Kamen Rider Ex-Aid comes in and fights the bugsters while helping innocent people. As he brings each bugster down, he prepares to finish them.)

Ex-Aid: Eat this!

GASHAT! KIMEWAZA! MIGHTY CRITICAL STRIKE!

(Ex-Aid covers his right foot in turquoise energy before leaping into the air and delivering a kick to the bugsters causing them all to explode.)

GAME CLEAR!

(Then Ex-Aid leaves, but his fight was noticed by a certain girl.)

Neptune: Whoever is this guy, he's interesting.

(Prologue Ends)