wotc
If Chandra's Pyrohelix targets two creatures and one becomes an illegal target, the remaining target is dealt 1 damage, not 2.
If Chandra's Pyrohelix targets two creatures and one becomes an illegal target, the remaining target is dealt 1 damage, not 2.
You divide the damage as you cast Chandra's Pyrohelix, not as it resolves. Each target must be assigned at least 1 damage. In other words, as you cast Chandra's Pyrohelix, you choose whether to have it deal 2 damage to a single target, or deal 1 damage to each of two targets.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Aleksi Briclot
Card data via Scryfall. Rarix is fan-made; not endorsed by the rights holders.