The Red Terror 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

Advanced Species — Whenever a red source you control deals damage to one or more permanents and/or players, put a +1/+1 counter on The Red Terror.

Complete guide

The Red Terror is a formidable Tyranid that thrives on the chaos of battle, growing stronger with every spark of red magic. By monitoring whenever your red sources deal damage, this creature can quickly scale into a game-ending threat. Let's explore how to maximize its potential and ensure you never miss a counter.

Understanding Advanced Species

The Red Terror features the Advanced Species ability, which triggers whenever a red source you control deals damage to one or more permanents or players. It is important to note that 'red source' includes red creatures, red spells, and even red enchantments or artifacts if they have a red color identity. The ability triggers once per event, regardless of how much damage is dealt, as long as at least one point of damage is marked on a valid target.

Step-by-Step Resolution

First, a red source you control (like a red creature in combat) deals damage. Second, The Red Terror's triggered ability goes on the stack. Third, players have the chance to respond with spells or abilities. Finally, as the ability resolves, you place a single +1/+1 counter on The Red Terror. If a single red source deals damage to multiple targets simultaneously, such as through Trample or an area-of-effect spell, it still only triggers once for that specific damage event.

Common Mistakes to Avoid

A common misconception is that dealing five damage results in five counters; however, the ability cares about the 'event' of dealing damage, not the quantity. Additionally, remember that The Red Terror is itself a red source. If it deals combat damage, it will trigger its own ability and grow larger. Also, non-red sources you control, such as colorless artifacts, will not trigger this ability even if they are attacking alongside the Tyranid.

When to Play The Red Terror

This creature is best utilized in decks with high-frequency damage output. It excels in aggressive red shells where multiple creatures or spells are dealing damage every turn. Because it triggers on damage to permanents as well as players, it remains relevant even if your opponent is successfully blocking your attacks.

Interaction examples

Doubling the Growth

Roaming Throne

First, you cast Roaming Throne and choose 'Tyranid' as the creature type. When The Red Terror (a red source) deals damage to an opponent, its Advanced Species ability triggers. Because Roaming Throne is on the battlefield, the ability triggers an additional time. You will resolve two separate instances of the ability, putting a total of two +1/+1 counters on The Red Terror instead of one.

Colorless Interaction

Solemn Simulacrum

Suppose you attack with both The Red Terror and Solemn Simulacrum. Both creatures deal combat damage to the defending player simultaneously. The Red Terror's ability checks the sources of damage. Since The Red Terror is red, it triggers its own ability. However, because Solemn Simulacrum is a colorless artifact, its damage does not satisfy the 'red source' requirement. You only put one +1/+1 counter on The Red Terror.

Self-Sustaining Combat

When The Red Terror attacks and is not blocked, it deals combat damage to the player. As a red creature, it counts as a red source. This triggers its own Advanced Species ability, causing it to gain a +1/+1 counter immediately after the damage step. This makes it a 5/5 or larger for the next turn's combat.

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