They're exiled at the end of the turn, but you get a leaving-the-graveyard trigger, an ETB trigger, and a leaves-play trigger
Grist, The Hunger Tide: An extremely unique planeswalker that's also a tiny insect
Even for a relatively simple and un-interactive effect like self-mill, there are a dizzying number of ways to achieve it and all sorts of secondary considerations which might sway you towards one solution over another
Its Azorius color identity means you have access to most of the best pillows, and the may clause on its activated ability means you literally cant lean on it as a win condition to mill your opponents libraries away
Grading companies call out Shadowless on the label, and that single word can change value quickly for key cards like Charizard, Blastoise, and Venusaur
they are Characters , Items and Actions