If a unit has 3 damage on it from Iron Ballista, then Smoke Screen is played reducing its might to 3, does the unit die?

Ruling: Yes, the unit would die. If non-zero damage is ever equal to or greater than might, the unit dies.

Sequence:

• Unit receives 3 damage from Iron Ballista
• Smoke Screen is played, reducing the unit's might to 3
• Since the damage (3) equals the might (3), the unit dies