Ertai's Familiar {1}{U}
Creature — Illusion
Phasing (This phases in or out before you untap during each of your untap steps. While it's phased out, it's treated as though it doesn't exist.)
When this creature phases out or leaves the battlefield, mill three cards.
{U}: Until your next upkeep, this creature can't phase out.
click a line to search just that ability, click more to combine them
Cards that do something similar expected a card that isn't here?
Reports become test cases the matcher is graded against before an update ships. Delvefall isn't a chatbot guessing, it compares the printed rules text of every card with plain math, and examples like yours decide which differences should count.