Subrule · Chapter 9
cr:9.1.2c
If an effect applies to a double-faced card, it continues to apply to the card even if its properties are defined by a different face, as long as it does not cease to exist between changing properties.
Example: Oasis Respite has the text “Prevent the next 4 damage that would be dealt to target hero this turn by a source of your choice.” If a flip-card card with its front-face active is chosen as the source, then the flip-card resolves, enters the arena, and its back-face becomes active, it is still subjected to Oasis Respite’s effect.