The Battle Zone is the gameplay zone between your shields and your opponent's shields.
Creatures are put into this area where they can battle other creatures or attack players. Spells that are cast are put into this area before they take effect. Cross gears are generated into this area where they can then be crossed onto other creatures. There is no limit to the number of cards that can be in the battle zone.
403.1. Battle Zone is the main place of the game. Creatures, Cross Gears, Weapons, Fortressess, Beats and Fields are put into the battle zone, but no mana, shields, castles nor spells may be put into the battle zone.
403.2. Creatures in the battle zone can be arranged however their owners wish, although it must remain clear to all players which creatures cross gears and weapons belong to.
403.3. Players can rearrange their cards in the battle zone at any time.