Corum Assassin

Quickness (This Unit can attack or activate Exhaust abilities the turn it is played.)
Arrive (When this card enters the field zone.) – You can sacrifice a Gear you control to destroy target Unit your opponent controls.

Q: Does Corum Assassin’s Arrive ability need to sacrifice a Gear as a cost?
A: No. When the Arrive ability goes on the Queue, you select which target unit you are attempting to destroy. When the ability resolves, you may sacrifice a Gear, and the unit is destroyed. If you don’t control a Gear, or if you choose not to sacrifice one, then the unit is not destroyed. (See costs of triggered abilities –
Q: If my opponent takes control of a unit I control that I equipped with a Gear, can I sacrifice that Gear with Corum Assassin’s ability?
A: No. Equipped augments, including Gear, are controlled by the player that controls the equipped unit. (See Controller – 1.2.3 and augments that Equip –
Left Menu Icon