Mystic Retrieval — ruling 1

To determine the total cost of a spell, start with the mana cost or alternative cost (such as a flashback cost) you're paying, add any cost increases, then apply any cost reductions. The mana value of the spell is determined only by its mana cost, no matter what the total cost to cast the spell was.

Mystic Retrieval — ruling 2

"Flashback [cost]" means "You may cast this card from your graveyard by paying [cost] rather than paying its mana cost" and "If the flashback cost was paid, exile this card instead of putting it anywhere else any time it would leave the stack."

Mystic Retrieval — ruling 3

You must still follow any timing restrictions and permissions, including those based on the card's type. For instance, you can cast a sorcery using flashback only when you could normally cast a sorcery.

Mystic Retrieval — ruling 4

If a card with flashback is put into your graveyard during your turn, you can cast it if it's legal to do so before any other player can take any actions.

Mystic Retrieval — ruling 5

A spell cast using flashback will always be exiled afterward, whether it resolves, is countered, or leaves the stack in some other way.

Mystic Retrieval — ruling 6

You can cast a spell using flashback even if it was somehow put into your graveyard without having been cast.

Mystic Retrieval — ruling 7

Mystic Retrieval can't target itself. It's on the stack when you choose its target.

Mystic Retrieval : règles, fonctionnement et interactions (MTG)

Mystic Retrieval is one of those cards players keep asking about. Here is, in plain words, what its official text says, the rulings published by Wizards of the Coast, and the combos players actually run.

Official card text

Return target instant or sorcery card from your graveyard to your hand. Flashback (You may cast this card from your graveyard for its flashback cost. Then exile it.)

How it works : Mystic Retrieval

Original English text — Wizards of the Coast / Scryfall

#1March 19, 2021· Wizards of the Coast
To determine the total cost of a spell, start with the mana cost or alternative cost (such as a flashback cost) you're paying, add any cost increases, then apply any cost reductions. The mana value of the spell is determined only by its mana cost, no matter what the total cost to cast the spell was.
No other card is named in this ruling.
#2March 19, 2021· Wizards of the Coast
"Flashback [cost]" means "You may cast this card from your graveyard by paying [cost] rather than paying its mana cost" and "If the flashback cost was paid, exile this card instead of putting it anywhere else any time it would leave the stack."
No other card is named in this ruling.
#3March 19, 2021· Wizards of the Coast
You must still follow any timing restrictions and permissions, including those based on the card's type. For instance, you can cast a sorcery using flashback only when you could normally cast a sorcery.
No other card is named in this ruling.
#4March 19, 2021· Wizards of the Coast
If a card with flashback is put into your graveyard during your turn, you can cast it if it's legal to do so before any other player can take any actions.
No other card is named in this ruling.
#5March 19, 2021· Wizards of the Coast
A spell cast using flashback will always be exiled afterward, whether it resolves, is countered, or leaves the stack in some other way.
No other card is named in this ruling.
#6March 19, 2021· Wizards of the Coast
You can cast a spell using flashback even if it was somehow put into your graveyard without having been cast.
No other card is named in this ruling.
#7January 22, 2011· Wizards of the Coast
Mystic Retrieval can't target itself. It's on the stack when you choose its target.
No other card is named in this ruling.