If the spell has damage divided as it was cast (also like Avacyn's Judgment), the division can't be changed (although the targets receiving that damage still can).
Geistblast
Geistblast's ability can copy any instant or sorcery spell, not just one with targets.
The copy will have the same targets as the spell it's copying unless you choose new ones. You may change any number of the targets, including all of them or none of them. If, for one of the targets, you can't choose a new legal target, then it remains unchanged (even if the current target is illegal).
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Raymond Swanland
Card data via Scryfall. Rarix is fan-made; not endorsed by the rights holders.
