Who else thinks this stage should show up? Taking place in the throne room (where you face Zant), it could have how we view the stage occasionally change between regular and Sense, and the Usurper King himself could sit on the throne in the background, watching, reacting to the battle (like laughing when someone dies, shrieking agitatedly when someone just barely recovers) and even interacting with it by summoning Shadow Keese to bother the fighters or making Shadow Deku Babas sprout and attack.