Once Upon a Time
Instant
If this spell is the first spell you've cast this game, you may cast it without paying its mana cost.
Look at the top five cards of your library. You may reveal a creature or land card from among them and put it into your hand. Put the rest on the bottom of your library in a random order.
Matt Stewart
The List (PLST)
• #ELD-169Rulings
The earliest opportunity you have to cast Once Upon a Time is during the first player's upkeep, before that player can play a land.
(wotc • 2019-10-04)
Rulings
The earliest opportunity you have to cast Once Upon a Time is during the first player's upkeep, before that player can play a land.
(wotc • 2019-10-04)