When a unit is defending alone with Yi's +2 might bonus and gets attacked by Leona Zealot (which gives -8 might), does the +2 apply before the -8, or does the -8 overwrite the +2?

Ruling: Both are passive effects that apply simultaneously in the arithmetic layer. You add all bonuses first, then subtract all penalties, with a minimum of 1 might.

Sequence:

• Start with base might
• Add all bonuses (including Yi's +2)
• Subtract all penalties (including Leona's -8)
• Apply minimum of 1 might

Nuances:

• Yi's ability is a "While" effect, not a "When" effect, so it applies continuously
• In the arithmetic layer, addition comes before subtraction
• You need the base might plus additions to total more than 8 to avoid being reduced to 1 might by Leona's effect