It is gold and only wants to go in very aggressive decks
Assuming youve gained a bit of life already, the best way to guarantee your opponents wont benefit from Kain is to send 21 commander damage at them
shuffle that target into the Deck, and if you do, during the End Phase of this turn, its owner can add 1 monster from their Deck to their hand with a different Type and a Level lower than the Level/Rank/Link Rating of that monster
Simply put, it's because it doesn't add any restriction on how you can spend your mana
Featuring iconic characters such as Luffy, Shanks, Blackbeard, and Buggy, this expansion delivers some of the most desirable cards in the One Piece Card Game
There are certainly Commons that are good outside of draft