Disruptor Flute — ruling 1

You can choose the name of any card. You can't choose the name of a token unless it's also the name of a card.

Disruptor Flute — ruling 2

Some cards can have alternative names, such as split cards, adventurer cards, double-faced cards, and so on. You may choose one of the two names the card can have; Disruptor Flute's abilities won't affect anything with the other name. For example, if you choose Ondu Knotmaster, Throw a Line will still cost only {W}{B} to cast.

Disruptor Flute — ruling 3

To determine the total cost of a spell, start with the mana cost or alternative cost you're paying, add any cost increases, then apply any cost reductions. The mana value of the spell remains unchanged, no matter what the total cost to cast it was.

Disruptor Flute — ruling 4

If you name a card that has both a mana ability and another activated ability, the mana ability can be activated but the other ability can't be activated.

Disruptor Flute — ruling 5

Activated abilities contain a colon. They're generally written "[Cost]: [Effect]." Some keywords are activated abilities and will have colons in their reminder text. An activated mana ability is one that produces mana as it resolves, not one that costs mana to activate.

Disruptor Flute : règles, fonctionnement et interactions (MTG)

Disruptor Flute 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

Flash As this artifact enters, choose a card name. Spells with the chosen name cost more to cast. Activated abilities of sources with the chosen name can't be activated unless they're mana abilities.

How it works : Disruptor Flute

Original English text — Wizards of the Coast / Scryfall

#1June 7, 2024· Wizards of the Coast
You can choose the name of any card. You can't choose the name of a token unless it's also the name of a card.
No other card is named in this ruling.
#2June 7, 2024· Wizards of the Coast
Some cards can have alternative names, such as split cards, adventurer cards, double-faced cards, and so on. You may choose one of the two names the card can have; Disruptor Flute's abilities won't affect anything with the other name. For example, if you choose Ondu Knotmaster, Throw a Line will still cost only to cast.
No other card is named in this ruling.
#3June 7, 2024· Wizards of the Coast
To determine the total cost of a spell, start with the mana cost or alternative cost you're paying, add any cost increases, then apply any cost reductions. The mana value of the spell remains unchanged, no matter what the total cost to cast it was.
No other card is named in this ruling.
#4June 7, 2024· Wizards of the Coast
If you name a card that has both a mana ability and another activated ability, the mana ability can be activated but the other ability can't be activated.
No other card is named in this ruling.
#5June 7, 2024· Wizards of the Coast
Activated abilities contain a colon. They're generally written "[Cost]: [Effect]." Some keywords are activated abilities and will have colons in their reminder text. An activated mana ability is one that produces mana as it resolves, not one that costs mana to activate.
No other card is named in this ruling.