Maiden of Corantos

:Forerunner :［ 1‐card with "Maiden of" in its card name & Choose a card from your hand, and discard it］ At the end of the battle that this unit boosted ([Boost]) a rear-guard with "Maiden of" in its card name, if you have a face up card in your G zone or your vanguard is [Legion], you may pay the cost. If you do, choose one of your other rear-guards in the same column as this unit, it, and retire this unit.