How does Hextech Ray followed by Stupefy kill a unit when damage and Might are different?

Ruling: When a unit takes damage, that damage is marked on the unit without reducing its Might. If the unit's Might is then reduced (such as by Stupefy), the marked damage can exceed the new lower Might value, killing the unit.

Sequence:

• Hextech Ray deals 3 damage, marking 3 damage on the unit (Might unchanged)
• Stupefy reduces the unit's Might by 1
• If the unit was 4 Might, it becomes 3 Might with 3 damage marked, causing it to die

Nuances:

• This works similarly to Magic: The Gathering where damage marked on a creature persists when its toughness is reduced
• The order matters: Stupefy must be played after the damage is marked for this interaction to work