“夏の迷い子”うみ is a Weiß Schwarz card from PRカード【Wサイド】 SMP/W82-P01. Compare listings from Singapore Weiß Schwarz sellers on CardJio, then jio them on WhatsApp.
【AUTO】 When this card attacks, choose 1 of your other characters, and that character gets +X power until end of turn. X is equal to that character's soul ×1000.