Historical Rules · 14 April 2023
Rule 712.1
Official source text from the 14 April 2023 Rules release
A double-faced card has a Magic card face on one side and either a Magic card face or half of an oversized card face on the other. (It does not have a Magic card back.) There are three kinds of double-faced cards: transforming double-faced cards, modal double-faced cards, and meld cards.