Sealing Card

Sealing Cards (封印カード Fūin Kādo) are special cards that can absorb any non-physical energy, such as fire or explosions, and release them through various means. Said to be made from dragon skin, they are extremely rare and are generally sold for steep prices ranging from 100,000 to 100,000,000, depending on its quality.

Abilities
Sealing Cards can absorb any non-physical energy, such as fire or explosions, that comes in contact with its surface. While the card itself is usable as many times as possible, the energy has to be constantly resealed after use. Also, each card has a specific limit to how much energy it can hold; if exceeded, the card will violently explode and disintegrate.