Teferi, Master of Time is a mythic Legendary Planeswalker — Teferi card from Core Set 2021 (M21), collector number 293. Current market price: $9.20 (foil $8.58), TCGplayer market prices via Scryfall.
You may activate loyalty abilities of Teferi on any player's turn any time you could cast an instant. +1: Draw a card, then discard a card. −3: Target creature you don't control phases out. (Treat it and anything attached to it as though they don't exist until its controller's next turn.) −10: Take two extra turns after this one.