If a spell targets a unit, but the unit becomes an illegal target before the spell resolves (e.g., due to another spell making it untargetable), does the spell still deal damage?

Ruling: The spell still resolves, but it checks if the target is still valid before resolving. If the target is no longer valid, the spell will not deal any damage.

Sequence:

• Cast spell and choose target
• Pay all costs
• Before resolving, check if all chosen targets are still legal
• If target is illegal, spell resolves but does not deal damage

Nuances:

• The legality check happens after paying costs but before the card resolves and is removed from the chain