Whenever one or more other permanents phase out (While they're phased out, they're treated as though they don't exist. They phase in before you untap during your untap step.) and whenever one or more other cards are put into exile from anywhere, put a time counter on The War Doctor. Whenever The War Doctor attacks, it deals damage equal to the number of time counters on it to any target. If a creature dealt damage this way would die this turn, exile it instead.