Lets say a Mega Sableye used Will-O-Wisp on a Hatterene with Magic Bounce.
Hatterene bounces it back...
But Sableye-M... also has Magic Bounce...
Will they indefinitely bounce back the Will-O-Wisp? Or will the move fail?
Magic Bounce cannot active against moves that have already been Magic Bounced. In this instance, Hatterene would reflect Will-O-Wisp and Mega Sableye would be burned instead of reflecting it back.
Magic Bounce (Bulbapedia)
