They "remember" any counters they had on them, any choices made when they first came into play, and whether they were tapped or untapped when they left play
Given the Flash keyword, that can be a game changer if timed well
I was there at the Phyrexian invasion of Dominaria when the Nine Titans gave their lives, and I was there when the planeswalkers lost their sparks, and I was there when outside IP began slowly creeping its way into the classic trading card game so it is with some confidence and experience that I say Wizards of the Coast has finally figured it out with the MTG Final Fantasy set
Since its a repeatable powerhouse thats Flicker on a stick, as long as you can churn out the colorless mana, the Displacer is a major threat moving forward
I think we need to reframe Daretti a little in 2023, though because its less Trash for Treasure and more Treasure for Treasure
Perhaps also discard decks, like Inti, Seneschal of the Sun