[CONT]:
Sentinel
(You may only have up to four cards with "[CONT]: Sentinel" in a deck)
[AUTO]:[Choose an «
Aqua Force
» from your hand, and discard it] When this unit is placed on (GC), you may pay the cost. If you do, choose one of your «Aqua Force» that is being attacked, and that unit cannot be hit until end of that battle.
(BT08): Blue knights maintain the order, and the emerald shield will protect the knights.
(BT11): An Emerald Shield cannot be broken.