silver dialga pokemon card EX 122/119 on a rare single card. XY Phantom Forces 122/119 Dialga

Magic: The Gatherings Rarest Cards Of All Time 10 - Time Walk (Alpha) A card from the games Alpha Edition, Time Walk has sold for around $25,000 and offered an extra turn for a measly two mana, meaning it was banned pretty swiftly

Its an excellent way of making MTG fair again

Others don't tap for mana at all, like Bazaar of Baghdad and Diamond Valley

P/T Set Number 181 Language Espaol Legal Formats Brawl, Commander, Competitive Brawl, Historic, Legacy, Modern, Pauper, Pioneer, Timeless, Vintage Not Legal Formats Alchemy, Standard Rulings (2/18/2022) Discarding the card is part of the cost to activate a channel ability