Snap Fingers

When activating Snap Fingers’ ability, you must target an attack action card you control with the Lightning supertype on the active chain link. When Snap Fingers’ activated ability resolves, that card will deal 1 arcane damage to the defending hero.

If you are a defending hero, you can activate Snap Fingers’ ability and target a defending Lightning attack action card you control on the combat chain. In this scenario, when Snap Fingers’ activated ability resolves, that targeted card will deal you 1 arcane damage as you are the defending hero. Moreover, if that targeted card had an ability with a triggering condition when damage is dealt (e.g. when this deals damage), that ability would not trigger as that ability is not functional while defending (unless otherwise stated).

If the targeted Lightning attack action card’s attack-target is an ally, the defending hero will be its controller.

You would not be able to activate this in the layer step or resolution step of a chain link as this ability requires you to target a Lightning attack action card you control on the active chain link. When a chain link is created during the Attack Step it remains the active chain link until it resolves (at the beginning of the resolution step) or the combat chain closes.