polymorphous rush

[particle]

was drafting at my lgs and was watching a game where a player was trying to cast {polymorphous rush} turning his creatures into his opponents {keranos, god of storms} who was actually active. now i learned that he could make them all keranos' but they would also copy the legendary status and all but one would be sacked. so now i looked at the gatherer to try to understand {polymorphous rush} some more. so the gatherer says that you only choose which creature is being copied during resolution. so my question is how would i know that the choice should be made upon resolution or upon declaring targets? can you provide examples of when you when choose during targets vs choose during resolution? thanks.

[Pleeb]

Targets are chosen when the spell is cast as part of puting it on the stack and so are always chosen as you cast the spell. If it doesn't target, you make the choice as the spell resolves as there are no choices to make until then.

[Mr_Fahrenheit]

Except in cases where the card specifically says otherwise. Like {banishing light} or {oblivion ring}. Generally if it's not an aura or an instant or sorcery that needs a target to resolve then targets are declared after it resolves. The card itself will usually state what needs to happen and when.

[particle]

sorry guys i didnt realize the card just said choose a creature. thought the creature being chosen was targetted but its not.

[Pleeb]

No worries. I misread cards all the time.