"Dash [cost]" means "You may cast this card by paying [cost] rather than its mana cost," "If this spell's dash cost was paid, return the permanent this spell becomes to its owner's hand at the beginning of the next end step," and "As long as this permanent's dash cost was paid, it has haste." If you choose to pay the dash cost rather than the mana cost, you're still casting the spell
This is one of the most unique creature typings the game has seen in a while
The side deck particularly emphasizes this - we'd prefer to go first, but if you make us go second you might actually have a worse time in some circumstances
Threats such as Sen Triplets and Yurlok of Scorch Thrash can be cast thanks to this formidable 5-color sorcery
The Japanese versions are gorgeous and far more desirable than the global art versions, as well as being in lesser supply in the first place
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