|This article is about a/an A.R. World event in Kamen Rider Decade.|
The Kamen Rider Trial (仮面ライダー裁判 Kamen Raidā Saiban), also referred to as the Rider Battle (ライダーバトル Raidā Batoru), is a battle event for Riders in the World of Ryuki in which Kamen Riders fight to determine who represents a defendant in a court of law to determine their innocence or guilt or if they deserve such a fate. The victor of which gets to appear in court to testify on behalf of or against the defendant. Unlike the original Ryuki's world, fighting in the Mirror World does not lead to death. A Rider who loses will be forcibly ejected from Mirror World, and their Advent Deck will also be destroyed. It is also against the rules to use Advent Cards or Contract Monsters outside of the Mirror World, as injury or death is a possibility for the parties involved if they use their attacks there as well as be liable to hurt civilians.