"What am I doing? Is this really me? Why are all the Riders attacking me? Why is this fight happening? No...No..NO!!
After all the Riders was defeated, I went to Natsumi. There was one Rider who wasn't fallen yet. Kamen Rider Kuuga. He change into his Ultimate Darkness form and I am still my original form. We cross paths and there was a light which was so bright until I woke up.
My name is Kadoya Tsukasa, a photographer. I don't have any memories of my past and I was save by an old man called Ejiro and living a young girl which is Natsumi. The dreams that I have, it's definitely not real though. I worked as a photographer and took many different kind of photos but the strange things is all the photos that came out is different like faces stick to faces. This cost me lots of trouble and there c1omes the angriest girl finding for me.
"What is this photos, Tsukasa?" Natsumi ask.
"Like I said. This is not my world too" I was wondering what joke am I making but to thing parallel world's exist? I am not sure by myself.
Suddenly, various holes in reality open, allowing the Orphnoch, Undead, Makamou, Worms,  Imagin, and Fangires to start terrorizing their world. "What's happening, Tsukasa?"
The creatures seperated us by putting a barrier and I can't go through of it. Then, my place suddenly change into a place where just a young man exist, Kurenai Wataru. "Where's your Belt and Book, Decade?" Just this few words I was wondering and wanted to ask but he dissapeared. I saw back Natsumi again running away from those creatures. In the bedlam, she finds a corroded belt and book, I recalled the belt at my dream and also the words that the guy said. The belt that destroys all Rider. "Is this my fate?" I ask myself but I have no choice to fight.
I call Natsumi "Give me the belt". She gave me the belt and allowing him to transform by using a card from the book and inserting it into the belt. "HENSHIN !" I transform to Kamen Rider Decade. The barriers broke and I fought those creatures. Using other cards, fight the various creatures that have invaded my reality by transforming into Kamen Riders Kabuto, Faiz, and Hibiki. Things comes true. After defeated them I came back in my own reality, I was warned by Wataru Kurenai that my reality is being superseded by the nine previous Kamen Riders' realities.
"You need to go through all the Rider's world and defeat all of them. Creation cannot be made without Destruction"
I need go to their worlds and defeat the other Kamen Riders to save my own world, while Wataru keeps it frozen in place. Back in the Hikari Studio, Eijiro reveals a large photo that shows another world. Stepping outside, I find myself in this world as a police officer while Kamen Rider Kuuga appears to aid the police against two Gurongi.
"Kamen Rider Kuuga. This is Kuuga world?"