Null Chamber 
World Enchantment
As this enchantment enters, you and an opponent each choose a card name other than a basic land card name. Spells with the chosen names can't be cast and lands with the chosen names can't be played.
Legality
standardNOT LEGALpioneerNOT LEGALmodernNOT LEGALlegacyLEGALvintageLEGALcommanderLEGAL