I couldn't find the document, but sometime during 1994 the Duelists' Convocation put out the very first mulligan rule
Appears in Flames of Destruction
their story ended before it could even begin
Then you can tap her with a green mana to make mana equal to your highest power, and with an X spell Hydra like an 7/7 you have already you now convert one to 7, and drop an 13 with that mana for the next one, draw and then have 13 even more and can win fast with their size or make enough mana to win with stuff like Staff of Possession, Fireball and other stuff
Whether you're an avid collector or a strategic player, these cards add a unique dimension to your collection
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