If I play Bellows Breath and target 3 units at a battlefield and then my opponent in reaction moves away from the battlefield, what happens?

When you play Bellows Breath and target three units at a battlefield, and your opponent reacts by moving some of those units away before the spell resolves, the spell does not automatically "fizzle." Instead, it follows the rules for targeting restrictions and resolution.

According to RiftJudge FAQ #7422 and FAQ #781, the "same location" requirement is a targeting restriction for playing the spell, not a requirement for resolution.

How it resolves:

1. Targeting: You choose up to three units at the same location when you play the spell. These targets are locked in at that time.
2. Movement: If your opponent uses a reaction to move some of those units to a different location (e.g., their base), the original group of targets no longer collectively fulfills the "same location" requirement.
3. Resolution: When Bellows Breath resolves, you must choose one location among those where your originally targeted units are currently present.
4. Damage: You deal 1 damage to all of your originally targeted units that are present at that chosen location. Any targeted units that moved to a different location (and are not at the chosen location) do not take damage.

Key Nuances:

• No Re-targeting: You cannot choose new targets after the spell has been played. You are limited to the units you originally selected.
• Subset Selection: You must choose a valid subset of your original targets that are all at the same location. You cannot split the damage between the battlefield and the base; you must pick one location and damage the targets present there.
• Repeat: If you paid the Repeat cost, the two instances of the spell resolve separately. The movement of a unit only affects the instance(s) where that unit was targeted.

This is based on the established RiftJudge FAQs #7422, #781, and #9018.