If a spell targets a unit on a battlefield, but a reaction moves it to base before the spell resolves, does the spell fizzle or does it still affect the unit?

Ruling: Cards and abilities do as much as they can. Even when a card does nothing because of an illegal target, it is still considered played.

Nuances:

• If a spell like Void Seeker targets a unit that gets moved by Retreat, you still draw the card from Void Seeker even though the unit is no longer a legal target
• The spell is still considered played for effects that care about playing cards (like Ravenbloom Student), even if the target becomes illegal