Neriv, Heart of the Storm — ruling 1

The damage is dealt by the same source as the original source of damage. The doubled damage isn’t dealt by Neriv unless it was the original source of damage.

Neriv, Heart of the Storm — ruling 2

If another effect (or effects) modifies how much damage a creature you control that entered this turn would deal (for example, by preventing some of that damage), the player being dealt damage or the controller of the permanent being dealt damage chooses the order in which any such effects, including the effect of Neriv’s last ability, apply. If all of the damage is prevented before the effect of Neriv’s last ability would apply, its effect no longer applies.

Neriv, Heart of the Storm — ruling 3

If damage dealt is being divided or assigned among multiple permanents or players, that damage is divided or assigned before any effects modify how much damage would be dealt. For example, say you control Neriv and you attack an opponent with a 5/5 creature with trample and haste that entered this turn. If it’s blocked by a 2/2 creature, you can assign 2 damage to the blocker and 3 damage to the defending player. Those amounts are then doubled to 4 and 6, respectively.

Neriv, Heart of the Storm : règles, fonctionnement et interactions (MTG)

Neriv, Heart of the Storm 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 If a creature you control that entered this turn would deal damage, it deals twice that much damage instead.

Complete guide

Neriv, Heart of the Storm is a powerful Spirit Dragon that turns your creatures' arrival into a devastating assault. By doubling the damage output of any creature you control that entered the battlefield this turn, Neriv rewards aggressive strategies and clever timing. This legendary flyer ensures that your reinforcements make an immediate and painful impact on your opponents.

Doubling the Impact

Neriv's primary ability is a replacement effect that watches for damage being dealt by creatures you control that entered the battlefield during the current turn. It doesn't matter how the damage is dealt—whether through combat, an activated ability, or a triggered ability—as long as the creature is new to the field, Neriv doubles the number. Note that the damage source remains the original creature, not Neriv itself.

Resolution and Interaction

When a creature that entered this turn deals damage, you don't 'respond' to the doubling; it happens automatically as the damage is dealt. If multiple effects modify damage (such as a prevention effect), the player being dealt damage or the controller of the permanent taking damage chooses the order in which those effects apply. Importantly, if you are assigning trample damage, you assign the original amount first, and then Neriv doubles the assigned values.

Strategic Timing

To maximize Neriv, you should focus on creatures with Haste or cards that enter the battlefield and immediately deal damage via triggered abilities. Because the effect only lasts for the turn the creature entered, you must ensure you have a way to utilize that creature immediately. Remember, if a creature leaves and re-enters the battlefield, it counts as a new object and will benefit from Neriv's doubling effect again that turn.

Interaction examples

Direct Combat with Roaming Throne

Roaming Throne

If you play Roaming Throne and choose 'Dragon', it becomes a Dragon in addition to its other types. If Roaming Throne attacks the same turn it enters (provided it gained haste), its base 4/4 stats would normally deal 4 damage. Because it entered this turn, Neriv replaces that 4 damage with 8 damage. While Roaming Throne's ability to double triggers doesn't affect Neriv's static replacement effect, the raw damage output is still doubled by Neriv.

Incidental Combat Support

Solemn Simulacrum

If you cast Solemn Simulacrum and give it haste, then attack with it, its 2 power would normally deal 2 damage. Because it entered the battlefield this turn, Neriv, Heart of the Storm doubles this to 4 damage. If Solemn Simulacrum were to deal non-combat damage through an outside effect during the same turn it entered, that damage would also be doubled.

The Power of Flight

If Neriv, Heart of the Storm enters the battlefield and gains haste, it even applies to itself! A 3/3 flyer usually deals 3 damage, but since it is a creature you control that entered this turn, Neriv will replace its own 3 damage with 6 damage during combat.

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

How it works : Neriv, Heart of the Storm

Original English text — Wizards of the Coast / Scryfall

#1April 4, 2025· Wizards of the Coast
The damage is dealt by the same source as the original source of damage. The doubled damage isn’t dealt by Neriv unless it was the original source of damage.
No other card is named in this ruling.
#2April 4, 2025· Wizards of the Coast
If another effect (or effects) modifies how much damage a creature you control that entered this turn would deal (for example, by preventing some of that damage), the player being dealt damage or the controller of the permanent being dealt damage chooses the order in which any such effects, including the effect of Neriv’s last ability, apply. If all of the damage is prevented before the effect of Neriv’s last ability would apply, its effect no longer applies.
No other card is named in this ruling.
#3April 4, 2025· Wizards of the Coast
If damage dealt is being divided or assigned among multiple permanents or players, that damage is divided or assigned before any effects modify how much damage would be dealt. For example, say you control Neriv and you attack an opponent with a 5/5 creature with trample and haste that entered this turn. If it’s blocked by a 2/2 creature, you can assign 2 damage to the blocker and 3 damage to the defending player. Those amounts are then doubled to 4 and 6, respectively.
No other card is named in this ruling.