Large Wheel of the Cosmos, Cosmo Wreath (G-EB03/037EN)

[G guardian] (Usable when both fighters' vanguards are grade 3 or greater, and the number of face up G guardians in your G zone is three or less) -Opponent Turn's Guard Step-[Choose a card with "Heal" from your hand, and discard it] Call this card to your (GC) from face down. [AUTO]:[Counter Blast (1)] When this unit is placed on (GC), you may pay the cost. If you do, your opponent chooses one of his or her rear-guards in the back row, and locks it. If a card was locked, this unit gets [Shield]+5000 until end of that battle.