Wildfire 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

Each player sacrifices four lands of their choice. Wildfire deals 4 damage to each creature.

How it works : Wildfire

Original English text — Wizards of the Coast / Scryfall

No additional ruling has been published for this card.

Interactions with other cards

These cards' text mentions Wildfire.

Wildfire Howl

Gift a card (You may promise an opponent a gift as you cast this spell. If you do, they draw a card before its other effects.) Wildfire Howl deals 2 damage to each creature. If the gift was promised, instead Wildfire Howl deals 1 damage to any target and 2 damage to each creature.