If I use Void Seeker to deal 4 damage to a 7 might unit, then use Smoke Screen to reduce it by 4 might, does the unit die?

Ruling: Yes, the unit will die during the next cleanup when the game checks if damage marked on it is greater than or equal to its might.

Sequence:

• Apply Void Seeker (4 damage) and Smoke Screen (-4 might) in either order
• During the next cleanup, the game checks if damage ≥ might
• The unit dies (4 damage ≥ 3 might)

Nuances:

• The order of applying damage and might reduction generally doesn't matter, as long as damage isn't healed between application and cleanup
• Order only matters for "when you kill with a spell" triggers: Smoke Screen first then damage counts as a spell kill, but damage first then Smoke Screen does not count as a spell kill