Teferi's Envoy

Whenever a permanent you control phases out or
in, scry 1.
At the beginning of your end step, put a phasing
counter on another target nonland permanent
you control. (Permanents with a phasing counter on
them phase 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.)
Unseen matters solve what the mind can't.