wotc
If the spell that targets Gossamer Phantasm has no other targets, it won't resolve (because it no longer has a legal target after Gossamer Phantasm has been sacrificed).
If the spell that targets Gossamer Phantasm has no other targets, it won't resolve (because it no longer has a legal target after Gossamer Phantasm has been sacrificed).
Gossamer Phantasm's triggered ability resolves before the spell that caused it to trigger. It resolves even if that spell is countered.
Magic: The Gathering · ™ & © Wizards of the Coast · Illus. Jon Foster
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