Tomb of the Spirit Dragon — ruling 1

Count the number of colorless creatures you control (including face-down creatures) as the last ability resolves to determine how much life you gain.

Tomb of the Spirit Dragon : règles, fonctionnement et interactions (MTG)

Tomb of the Spirit Dragon 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

: Add . , : You gain 1 life for each colorless creature you control.

How it works : Tomb of the Spirit Dragon

Original English text — Wizards of the Coast / Scryfall

#1September 20, 2014· Wizards of the Coast
Count the number of colorless creatures you control (including face-down creatures) as the last ability resolves to determine how much life you gain.
No other card is named in this ruling.