You must choose all the targets at the time you cast Put Away. You can’t use it to counter your own spell and then shuffle that card into your library because at the time you choose targets, the spell isn’t in your graveyard yet.
2008-05-01
wotc
If you choose to target a card in your graveyard, Put Away will have two targets. If either one of the targets becomes illegal, Put Away will continue to resolve and affect the other target.
2008-05-01
wotc
If the targeted spell can’t be countered, that spell will remain on the stack. Put Away will continue to resolve. If you targeted a card in your graveyard, you still get to shuffle it into your library.
Format Legality
Standard
Not Legal
Future
Not Legal
Historic
Not Legal
Timeless
Not Legal
Gladiator
Not Legal
Pioneer
Not Legal
Modern
Legal
Legacy
Legal
Pauper
Legal
Vintage
Legal
Penny
Not Legal
Commander
Legal
Oathbreaker
Legal
Standardbrawl
Not Legal
Brawl
Not Legal
Alchemy
Not Legal
Paupercommander
Legal
Duel
Legal
Oldschool
Not Legal
Premodern
Not Legal
Predh
Legal
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