Hidetsugu and Kairi — ruling 1

The two cards you put on top of your library can be from the three you just drew or ones that were already in your hand.

Hidetsugu and Kairi — ruling 2

The last triggered ability targets the opponent. If that player is an illegal target as the ability tries to resolve, the ability won’t resolve and none of its effects will happen. You won’t exile a card.

Hidetsugu and Kairi — ruling 3

You choose whether or not to cast the instant or sorcery card as the last triggered ability resolves. If you do, you do so as part of the resolution of that ability. You can’t wait to cast it later in the turn. Timing restrictions based on the card’s type are ignored.

Hidetsugu and Kairi — ruling 4

If you cast a card “without paying its mana cost,” you can’t pay any alternative costs. You can, however, pay additional costs. If the card has any mandatory additional costs, those must be paid to cast the card.

Hidetsugu and Kairi — ruling 5

If the card has {X} in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.

Hidetsugu and Kairi : règles, fonctionnement et interactions (MTG)

Hidetsugu and Kairi 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

Flying When Hidetsugu and Kairi enters, draw three cards, then put two cards from your hand on top of your library in any order. When Hidetsugu and Kairi dies, exile the top card of your library. Target opponent loses life equal to its mana value. If it's an instant or sorcery card, you may cast it without paying its mana cost.

How it works : Hidetsugu and Kairi

Original English text — Wizards of the Coast / Scryfall

#1April 14, 2023· Wizards of the Coast
The two cards you put on top of your library can be from the three you just drew or ones that were already in your hand.
No other card is named in this ruling.
#2April 14, 2023· Wizards of the Coast
The last triggered ability targets the opponent. If that player is an illegal target as the ability tries to resolve, the ability won’t resolve and none of its effects will happen. You won’t exile a card.
No other card is named in this ruling.
#3April 14, 2023· Wizards of the Coast
You choose whether or not to cast the instant or sorcery card as the last triggered ability resolves. If you do, you do so as part of the resolution of that ability. You can’t wait to cast it later in the turn. Timing restrictions based on the card’s type are ignored.
No other card is named in this ruling.
#4April 14, 2023· Wizards of the Coast
If you cast a card “without paying its mana cost,” you can’t pay any alternative costs. You can, however, pay additional costs. If the card has any mandatory additional costs, those must be paid to cast the card.
No other card is named in this ruling.
#5April 14, 2023· Wizards of the Coast
If the card has in its mana cost, you must choose 0 as the value of X when casting it without paying its mana cost.
No other card is named in this ruling.