Leona, Zealot
#OGN-079FoilIf an opponent's score is within 3 points of the Victory Score, I enter ready.
Stunned enemy units here have -8 
, to a minimum of 1 .
Errata & Clarifications
Q. Enemy 1 unit attacks my Leona, Zealot. Enemy plays a Switcheroo on their Focus, targeting their unit and my Leona. I then react with a spell that stuns the enemy unit.
All items resolve and showdown ends. What is the result of combat?
A. You would win combat. The original intention of this question was to ask how much Might the enemy unit would have: It would still be 1.
Leona is a passive ability and will ALWAYS apply the -8 as long as the unit stunned. Snapshotting would only endure (472.3.b.) until layers are reapplied and Leona's might reduction would reapply.
There is an argument that the snapshotting should only occur at the moment stun is applied. I would agree if it was a triggered ability, but Leona being a passive effect changes that notion due to layers always applying repeatedly (471.). With triggered abilities that reduce Might, they are a 1 time occurrence and their value is snapshotted for the duration of the turn. That said, the rules could do a better job clarifying how layers would apply when distinguishing between passive and triggered abilities.