Phyrexian Soulgorger — ruling 1

When Phyrexian Soulgorger’s cumulative upkeep ability resolves, you must either sacrifice a different creature for each age counter on Phyrexian Soulgorger or sacrifice it. You may also sacrifice it as part of its own upkeep payment.

Phyrexian Soulgorger : règles, fonctionnement et interactions (MTG)

Phyrexian Soulgorger 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

Cumulative upkeep—Sacrifice a creature. (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)

How it works : Phyrexian Soulgorger

Original English text — Wizards of the Coast / Scryfall

#1July 15, 2006· Wizards of the Coast
When Phyrexian Soulgorger’s cumulative upkeep ability resolves, you must either sacrifice a different creature for each age counter on Phyrexian Soulgorger or sacrifice it. You may also sacrifice it as part of its own upkeep payment.
No other card is named in this ruling.