Burst Seal (バースト封印, Baasuto Fuuin) is a keyword which debuted in BS38. The only spirit to possess it is The OxTwelveGodKing Avalanche-Bison. Similar to High Speed Seal, it combines Seal with another keyword, in this case, Burst:
- [Burst Seal: When Your Life is Decreased] When your Life is 3 or less, summon this Spirit without paying the cost. Afterwards, send (Soul Core) from one of your Spirits to your Life.
This keyword allows the player to surprise the opponent by summoning a God-King without paying the cost, as well as giving another method of Sealing on the opponent's turn.