The HeiseiKamen Rider 10th Anniversary (平成仮面ライダー10周年,Heisei Kamen Raidā Jusshūnen) was commemorated in 2009 with the broadcast of Kamen Rider Decade, the tenth entry of the revived Heisei Kamen Rider Series.
In an unprecedented move, the Decade TV series itself was wholly devoted to uniting all Heisei Kamen Rider series; the eponymous Kamen Rider, who is fated to one day destroy his predecessors in a Rider War, uses the Rider Cards to Kamen Ride into the forms of his predecessors. Throughout the series, Decade traveled through "A.R. Worlds" based on the settings of the prior series. Eventually, elements from the original Showa Rider series were incorporated as well.
In September, Decade was succeeded by Kamen Rider W, officially described as the Heisei Kamen Rider 10th Anniversary Project: Fall Campaign (平成仮面ライダー10周年プロジェクト 秋の陣,Heisei Kamen Raidā Jusshūnen Purojekuto: Aki no Jin).
Kamen Rider G was a one-off promotional work that not only celebrated the 10th anniversary of Heisei Riders, but also the 50th annniversary of TV Asahi.
Decade was also the first Kamen Rider season devoted to celebrating the franchise. There have been other seasons since Decade that celebrate the previous seasons. Namely Fourze, Zi-O and Revice.