Transform is an evergreen keyword used to describe an action that would change a card on the field or hand into a different card.

Description

Transforming a card results from an ability that causes an existing card to become a different card permanently, or until it leaves the game. Transformed cards are usually tokens, although regular cards can also be the result of a transformation.

Transformed cards do not become a shadow and their Last Words effects will not be activated. Also, transformation doesn't count as leave play.