Red Reign (SDCK-EN035) [Structure Deck: The Crimson King]

If you control a Level 8 or higher Synchro Monster: Banish all monsters on the field, except the monster(s) with the highest Level, also the remaining face-up monsters on the field are unaffected by other card effects, except their own, until the end of this turn. If a DARK Dragon Synchro Monster is Synchro Summoned to your field while this card is in your GY: You can add this card to your hand. You can only use this effect of "Red Reign" once per turn.