Rule 609.4a

If two effects state that a player may (or a creature can) do the same thing “as though” different conditions were true, both conditions could apply. If one “as though” effect satisfies the requirements for another “as though” effect, then both effects will apply. Example: A player controls Vedalken Orrery, an artifact that says “You may cast spells as though they had flash.” That player casts Shaman’s Trance, an instant that says, in part, “You may play lands and cast spells from other players’ graveyards this turn as though those cards were in your graveyard.” The player may cast a sorcery with flashback from another player’s graveyard as though it were in that player’s graveyard and as though it had flash.

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