Spoils of War — ruling 1

X is set as you cast the spell to be exactly the number of appropriate cards in an opponent’s graveyard. You can’t choose a higher or lower value for X.

Spoils of War : règles, fonctionnement et interactions (MTG)

Spoils of War 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

X is the number of artifact and/or creature cards in an opponent's graveyard as you cast this spell. Distribute X +1/+1 counters among any number of target creatures.

How it works : Spoils of War

Original English text — Wizards of the Coast / Scryfall

#1August 1, 2008· Wizards of the Coast
X is set as you cast the spell to be exactly the number of appropriate cards in an opponent’s graveyard. You can’t choose a higher or lower value for X.
No other card is named in this ruling.