Myr BattlesphereHow it works & interactions with other cards

Understanding the Myr Army

When Myr Battlesphere enters the battlefield, its first ability triggers, putting four 1/1 colorless Myr artifact creature tokens onto the field. These tokens are essential for its second ability, which triggers whenever the Battlesphere attacks. This attack trigger allows you to tap any number of untapped Myr you control—not just the tokens it created—to boost its power and burn your opponent.

Step-by-Step Resolution

First, you declare Myr Battlesphere as an attacker to put the ability on the stack. As the ability resolves, you choose a value for X based on your untapped Myr. You then tap those Myr all at once. The Battlesphere immediately gains +X/+0 and deals X damage directly to the player or planeswalker it is attacking. Note that the damage happens during the resolution of the trigger, well before the declare blockers or combat damage steps.

Common Mistakes and Rulings

A common misconception is that you need to tap the Myr before the ability resolves; however, you actually make the choice for X during resolution. You can tap Myr that have 'summoning sickness' because the ability is a cost of the trigger, not a 'Tap' ability on the Myr themselves. Even if Myr Battlesphere is destroyed in response to the trigger, the ability still resolves: you can still tap Myr to deal X damage, though the +X/+0 bonus will have no creature to apply to.

Strategic Timing

Because the damage from the attack trigger is direct, it is an excellent way to finish off an opponent who has a strong defensive line. Since you only tap the Myr upon resolution, your opponent must decide whether to use removal spells before they know exactly how many Myr you intend to tap. If you have other ways to create Myr, such as through Myr tokens, you can significantly scale the damage output beyond the initial four tokens.

Interaction examples

The Immediate Impact

Myr

1. Cast Myr Battlesphere and it enters the battlefield. 2. The enter-the-battlefield trigger creates four 1/1 Myr tokens. 3. On your next turn, you attack with Myr Battlesphere. 4. The attack trigger goes on the stack. 5. Upon resolution, you tap the four Myr tokens. 6. Myr Battlesphere gets +4/+0 (becoming an 8/7) and deals 4 damage directly to the opponent before blockers are even declared.

Responding to Destruction

Meteor Golem

1. You attack with Myr Battlesphere. 2. In response to the attack trigger, your opponent uses Meteor Golem's ability (via a flash effect or previous trigger) to destroy your Battlesphere. 3. The attack trigger remains on the stack. 4. As the trigger resolves, you still choose to tap your four Myr tokens. 5. Although the Battlesphere is gone and cannot gain +4/+0, the ability still deals 4 damage to the opponent.

Managing Different Artifacts

Wurmcoil Engine

1. You have Myr Battlesphere and Wurmcoil Engine on the battlefield. 2. You attack with both. 3. Only the Myr Battlesphere triggers. 4. Even though Wurmcoil Engine is a powerful artifact creature, it does not have the 'Myr' subtype, so it cannot be tapped to contribute to the Battlesphere's X value. Only creatures with the Myr type qualify.