Entwine

Entwine is a keyword ability appearing on modal instants and sorceries, ie. ones with the "Choose one —" clause. As you play a spell with entwine, if you pay the cost associated with it, instead of choosing one of the modes of the spell, it functions as though you chose both.

Spells with entwine were introduced in Mirrodin.

From the ()

Rulings

• You decide whether you're paying the entwine cost as you play the spell.
• If you choose not to pay the entwine cost, you can choose only one mode. If you choose to pay the entwine cost, you choose both modes.
• If you pay the entwine cost, choose targets for both modes as you play the spell. When the spell resolves, follow the instructions in the order they're written.
• For all modal spells that don't have entwine, you can choose only one mode. Only the entwine ability allows you to choose more than one mode.