Wrathful Red 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

Flying Whenever a Dragon you control is dealt damage, it deals that much damage to any target that isn't a Dragon.

Complete guide

Wrathful Red Dragon is a terrifying airborne threat that punishes your opponents for even thinking about hurting your team. With this Dragon on the board, every point of damage dealt to your scaly hoard is redirected back at your enemies or their non-Dragon permanents.

The Mechanics of Vengeance

Whenever a Dragon you control is dealt damage—whether from combat, a spell, or an ability—Wrathful Red Dragon triggers. It checks how much damage was dealt to that Dragon and then allows that Dragon to deal an equal amount of damage to any target that is not a Dragon. This can target players, planeswalkers, or other non-Dragon creatures.

Step-by-Step Resolution

First, damage must actually be dealt to a Dragon you control; if the damage is prevented, the ability does not trigger. Once damage is marked, the triggered ability goes on the stack and you choose a legal non-Dragon target. When the ability resolves, the Dragon that was originally hit is the source of the new damage. If that Dragon is no longer on the battlefield, the ability uses its last known information to determine its characteristics.

Important Considerations

A common mistake is trying to target another Dragon with the triggered ability; the text specifically says the target must be something that 'isn't a Dragon.' Additionally, if multiple Dragons are dealt damage simultaneously (like during combat or from a board wipe), Wrathful Red Dragon will trigger separately for each instance of damage dealt to each Dragon.

Strategy and Timing

Play this card when you have a board presence of other Dragons to create a 'no-win' situation for your opponent. It makes blocking your attackers disastrous for them and turns their damage-based removal spells into direct damage aimed at their own face.

Interaction examples

Multiplying the Fury

Roaming Throne

If you choose 'Dragon' for Roaming Throne, it becomes a Dragon. When Wrathful Red Dragon is dealt damage, its ability triggers. Because Roaming Throne is another Dragon you control and its type matches, the triggered ability triggers an additional time. You will get two instances of damage to distribute to non-Dragon targets.

The Iron Guardian's Stand

Solemn Simulacrum

If your opponent blocks your Wrathful Red Dragon with Solemn Simulacrum, the Dragon takes 2 damage. This triggers the Dragon's ability, allowing it to deal 2 damage to any non-Dragon target, such as the opponent directly. Even though Solemn Simulacrum dies and lets the opponent draw a card, they still take the reflected fire from your Dragon.

Guide written with AI from the official text and rulings. Official English text prevails.