Damage is not might
Two numbers that look interchangeable and are not. Getting them straight is the difference between a trade and a clean kill.
A unit dies when
it has at least 1 damage
and
damage ≥ its might
Remember
Damage is marked on a unit; might is what it takes to kill it. A unit dies only when it has at least 1 damage AND that damage is at least its might — so 0 might with nothing marked on it lives. The test is re-checked constantly, so dropping a unit’s might can kill it without dealing any damage at all. Damage is wiped at two moments and only two: the end of every combat, which heals every survivor to full, and the Ending phase of each turn. So softening a unit up only pays inside the same turn, and only before a fight rather than after one. Buffs are not damage, and neither moment touches them.