Human Torch 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

At the beginning of combat on your turn, if you've cast a noncreature spell this turn, Human Torch gains flying, double strike, and haste until end of turn. Whenever Human Torch attacks, you may pay . If you do, until end of turn, whenever he deals combat damage to an opponent, he deals that much damage to each other opponent.

How it works : Human Torch

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 Human Torch.

Human Torch, Johnny Storm

Flying Whenever you draw a card, if you control another Hero, Human Torch deals 1 damage to target opponent. Power-up — {6}{R}: Put three +1/+1 counters on Human Torch. (Activate each power-up ability only once. Reduce the cost by his mana cost if he entered this turn.)