Peace in the Valley (Strahd)

Vanishing
When Peace in the Valley enters the battlefield,
each player puts all cards exiled with trapped
counters on them into their graveyard, then you
put a time counter on Peace in the Valley for
each card put into graveyards this way.
When Peace in the Valley enters a graveyard
from the battlefield, if it had no time counters
on it, exile it then return it to the battlefield transformed.