Can you react when equipment is being attached?

Ruling: Whether you can react depends on how the equipment is being attached.

Sequence:

• Using the Equip activated ability: Yes, you can react. Activating Equip places the ability on the chain, creating a closed state where players can respond with Reaction cards or abilities. If the target unit is removed before resolution, the equipment fails to attach.
• Playing equipment with Quick-Draw: You cannot react to the gear card entering play, but you can react to the attachment trigger. When you play a Quick-Draw gear, it enters at your base immediately. Then its "When you play this, attach it to a Unit you control" triggered ability goes on the chain, creating a closed state where opponents can respond. If the target is removed, the gear remains unattached at your base.
• Playing standard gear: The gear enters play and attaches immediately without using the chain, so there is no reaction window.

Nuances:

• Quick-Draw creates two distinct moments: the gear entering (no reaction window) and the attachment trigger (reaction window).
• Effects that say "Equip" use the activated ability and can be reacted to; effects that say "attach" typically happen immediately.