Tsukasa Kadoya (門矢 士, Kadoya Tsukasa) is an antagonist of Kamen Rider: Climax Heroes. He is an evil version of his present day self from the past who was the leader of Dai-Shocker as Kamen Rider Dark Decade (仮面ライダーダークディケイド, Kamen Raidā Dāku Dikeido) before he lost his memories.