What it does
Buyback appears on instants and sorceries as an additional cost—you pay extra (mana, sometimes life) when casting the spell. If you paid the buyback cost, the spell returns to your hand as it resolves instead of going to the graveyard. This lets you cast it again and again, as long as you can keep paying.
The nuance people miss: buyback is an additional cost, paid as part of casting, so you decide when putting the spell on the stack. If the spell is countered, it doesn't come back—you only get it back if it resolves. Also, you still get the full effect each cast; buyback only changes where it goes afterward.
In Commander, buyback shines as repeatable value or as a wincon engine—cards like Capsize with infinite mana lock opponents out by bouncing their permanents endlessly.













