If Foxfire targets a unit on the battlefield (chain 1), then the opponent moves that unit back to base (chain 2), does the damage still resolve, fizzle, or does the caster choose a new target?

Ruling: The spell will still resolve, but nothing will happen because Foxfire specifically requires the unit to be at a battlefield.

Nuances:

• The spell does not fizzle completely, it just has no effect
• No new target is chosen