Pyreswipe Hawk — ruling 1

The value of X is calculated only once, as Pyreswipe Hawk's third ability resolves.

Pyreswipe Hawk — ruling 2

If Pyreswipe Hawk leaves the battlefield before its last ability resolves, control of the target artifact won't change at all.

Pyreswipe Hawk — ruling 3

Abilities that trigger whenever you "expend N" only trigger when you reach that specific amount of mana spent on casting spells that turn. This can only happen once per turn. For example, if you've spent three mana on spells so far this turn and you control a permanent with an ability that triggers "whenever you expend 4," that ability will trigger the next time you spend at least one mana to cast a spell this turn. It won't trigger again if you spend another four mana to cast spells later in the turn.

Pyreswipe Hawk — ruling 4

If the cost to cast a spell is increased, decreased, or changed because of additional or alternative costs, expend counts only the mana you actually spent.

Pyreswipe Hawk — ruling 5

A permanent with an ability that triggers whenever you "expend N" will see mana you spent to cast spells the turn it enters, including mana you spent before it entered. For example, if you cast Junkblade Bruiser (a creature with a mana value of 5 and an ability that triggers whenever you expend 4) by paying its full cost of five mana, you'll already have spent four mana on spells before Junkblade Bruiser enters, and therefore its ability that triggers whenever you expend 4 won't be able to trigger at all that turn.

Pyreswipe Hawk : règles, fonctionnement et interactions (MTG)

Pyreswipe Hawk 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, haste Whenever this creature attacks, it gets +X/+0 until end of turn, where X is the greatest mana value among artifacts you control. Whenever you expend 6, gain control of up to one target artifact for as long as you control this creature. (You expend 6 as you spend your sixth total mana to cast spells during a turn.)

How it works : Pyreswipe Hawk

Original English text — Wizards of the Coast / Scryfall

#1July 26, 2024· Wizards of the Coast
The value of X is calculated only once, as Pyreswipe Hawk's third ability resolves.
No other card is named in this ruling.
#2July 26, 2024· Wizards of the Coast
If Pyreswipe Hawk leaves the battlefield before its last ability resolves, control of the target artifact won't change at all.
No other card is named in this ruling.
#3July 26, 2024· Wizards of the Coast
Abilities that trigger whenever you "expend N" only trigger when you reach that specific amount of mana spent on casting spells that turn. This can only happen once per turn. For example, if you've spent three mana on spells so far this turn and you control a permanent with an ability that triggers "whenever you expend 4," that ability will trigger the next time you spend at least one mana to cast a spell this turn. It won't trigger again if you spend another four mana to cast spells later in the turn.
No other card is named in this ruling.
#4July 26, 2024· Wizards of the Coast
If the cost to cast a spell is increased, decreased, or changed because of additional or alternative costs, expend counts only the mana you actually spent.
No other card is named in this ruling.
#5July 26, 2024· Wizards of the Coast
A permanent with an ability that triggers whenever you "expend N" will see mana you spent to cast spells the turn it enters, including mana you spent before it entered. For example, if you cast Junkblade Bruiser (a creature with a mana value of 5 and an ability that triggers whenever you expend 4) by paying its full cost of five mana, you'll already have spent four mana on spells before Junkblade Bruiser enters, and therefore its ability that triggers whenever you expend 4 won't be able to trigger at all that turn.
No other card is named in this ruling.