Vertigo

Ryu's gaze flashed with a blinding light and his senses felt as though a flash bang had gone off. It took much longer than normal for it to clear, something that was decidedly odd for him considering he was so used to his eyes being powerful. 

When he could see again, he found himself in a world of vast whiteness. It was hard to tell if there was a real floor beneath him, the ceiling didn't seem to have a limit, and he couldn't sense any walls. It was impossible to tell if he'd smack into a solid wall after one step or a million steps. 

'What the hell is this?'

Ryu felt that there was a non-zero chance that he had failed. In context, it didn't make any sense, but there was really no telling. If rules were hidden, this might very well be a punishment that he didn't know about.