HydrosurgeHow it works & interactions with other cards

What it Does

Hydrosurge is an instant that targets one creature on the battlefield. When it resolves, that creature loses 5 power until the end of the current turn. It does not affect the creature's toughness, meaning the creature stays on the board but deals significantly less damage in combat.

Step-by-Step Resolution

First, you cast Hydrosurge and choose a legal target creature. Next, players have the chance to respond with spells or abilities. If Hydrosurge resolves, the -5/-0 effect is applied immediately. If this reduction brings the creature's power below zero, its power is treated as zero for calculating damage, though it remains numerically negative for other effects.

Common Mistakes

A common error is thinking Hydrosurge removes a creature from combat. It does not; it only reduces damage. Additionally, if the targeted creature gains 'Hexproof' or 'Protection from Blue' in response, Hydrosurge will fail to resolve because its only target has become illegal.

When to Play It

The best time to use Hydrosurge is during the Declare Blockers step. This allows you to bait your opponent into an unfavorable trade, ensuring your small blocker survives a clash with their large attacker.

Interaction examples

Defending Your Assets

Counterspell

If you cast Hydrosurge to save your life from a 5/5 creature, your opponent might try to stop you with Counterspell. If Counterspell resolves, Hydrosurge is put into its owner's graveyard and the creature retains its full 5 power. You must ensure Hydrosurge actually resolves to get the -5/-0 benefit.

Navigating the Stack

An Offer You Can't Refuse

Because Hydrosurge is a noncreature spell, an opponent can target it with An Offer You Can't Refuse. If they do, Hydrosurge is countered and you will not reduce the creature's power, but you will create two Treasure tokens as consolation. This can be a strategic pivot if you need mana more than a combat trick.

Solo Combat Trick

In a simple scenario with just Hydrosurge, you can target an attacking 4/4 creature. Its power becomes -1/4 until end of turn. When it deals combat damage, it deals 0 damage, effectively protecting you or your planeswalkers for the turn.