Does Mask of Foresight trigger if you have two units on Reavers Row and use Reavers Row's ability to recall one unit first, leaving the other defending alone?

Ruling: No, this does not work. When defender triggers happen, they all trigger at the same time based on the game state at that moment. Since both units are defending when triggers are checked, Mask of Foresight never triggers because the unit is not defending alone at that point.

Sequence:

• Both units are declared as defenders
• All "When You Defend" triggers check simultaneously
• Mask of Foresight does not trigger because the unit is not defending alone at this moment
• Even if Reavers Row resolves first and recalls one unit, it's too late for Mask to trigger

Nuances:

• Mask of Foresight is not a passive effect that continuously checks game state; it only checks when triggers initially occur
• You do control the order that simultaneous triggers resolve, but this doesn't help because Mask never triggers in the first place
• Attack/defend abilities only activate when a unit is declared attacker/defender for the first time per combat, so recalling and bringing back a unit in the same showdown won't trigger them again
• If the opponent recalls their unit with Reavers Row after your unit was already declared an attacker, your unit keeps any buffs from Mask for the rest of combat