Mystic Plazma Zone

Field Spell cards allow you to modify the strength of all applicable Monsters on the field, both your own and your opponent's. They must be Set or activated in the Field Card Zone and only one Field Card can be activated at one time. When your opponent activates a new Field Card, then your Field Card must be sent to the Graveyard. You cannot Set or activate a new Field Card of your own until your current Field Card is destroyed.