Katilda and Lier — ruling 1

“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.”

Katilda and Lier — ruling 2

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.

Katilda and Lier — ruling 3

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.

Katilda and Lier — ruling 4

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

Katilda and Lier — ruling 5

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

Katilda and Lier — ruling 6

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.

Katilda and Lier — ruling 7

If you cast an instant or sorcery with {X} in its mana cost this way, you still choose the value of X as part of casting the spell and pay that cost.

Katilda and Lier — ruling 8

If you cast a spell with flashback, you can’t pay any alternative costs such as overload costs. You can pay additional costs such as kicker costs. If the spell has any mandatory additional costs, you must pay those to cast the spell with flashback.

Katilda and Lier : règles, fonctionnement et interactions (MTG)

Katilda and Lier 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

Whenever you cast a Human spell, target instant or sorcery card in your graveyard gains flashback until end of turn. The flashback cost is equal to its mana cost. (You may cast that card from your graveyard for its flashback cost. Then exile it.)

How it works : Katilda and Lier

Original English text — Wizards of the Coast / Scryfall

#1April 14, 2023· 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.
#2April 14, 2023· 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.
#3April 14, 2023· 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.
#4April 14, 2023· 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.
#5April 14, 2023· 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.
#6April 14, 2023· 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.
#7April 14, 2023· Wizards of the Coast
If you cast an instant or sorcery with in its mana cost this way, you still choose the value of X as part of casting the spell and pay that cost.
No other card is named in this ruling.
#8April 14, 2023· Wizards of the Coast
If you cast a spell with flashback, you can’t pay any alternative costs such as overload costs. You can pay additional costs such as kicker costs. If the spell has any mandatory additional costs, you must pay those to cast the spell with flashback.
No other card is named in this ruling.
#9April 14, 2023· Wizards of the Coast
If a card has multiple instances of flashback, you may choose any of its flashback costs to pay.
No other card is named in this ruling.
#10April 14, 2023· Wizards of the Coast
If a card with no mana cost gains flashback, it has no flashback cost. It can’t be cast this way.
No other card is named in this ruling.