Finn: What Was Missing is a Weiß Schwarz card from Adventure Time AT/WX02-007. Compare listings from Singapore Weiß Schwarz sellers on CardJio, then jio them on WhatsApp.
【CONT】 All of your other 《Ooo》 characters get +500 power and 《Music》. 【AUTO】 When this card is placed on the stage from your hand, reveal your hand, and this card gets 《Music》 until end of turn. 【ACT】 Brainstorm [(1) 【REST】 this card] Flip over 4 cards from the top of your deck, and put them into your waiting room. For each climax revealed among those cards, search your deck for up to 1 《Ooo》 character, reveal it to your opponent, put it into your hand, and shuffle your deck.