奏の残した言葉 is a Weiß Schwarz card from 戦姫絶唱シンフォギアG SG/W27-098. Compare listings from Singapore Weiß Schwarz sellers on CardJio, then jio them on WhatsApp.
Draw up to one card, choose one of your characters, and that character gets +2000 power until end of turn. Put this card into your memory.