How does Ahri Fox Fire's targeting work, and can damage be redistributed after opponent reactions?

Ruling: Ahri Fox Fire targets any number of units as long as the total might of all units is less than or equal to 4. After the opponent reacts with spells/buffs, the Ahri player chooses a subset of the originally selected targets (not redistributing damage, but selecting which targets to affect).

Sequence:

• Select any number of units with total might ≤ 4 as targets
• Opponent can react with spells/buffs when allowable
• Ahri player then chooses a subset of the selected targets

Nuances:

• Technically you don't redistribute damage; you choose a subset of targets from those originally selected