Tezzeret, Agent of Bolas is a mythic Legendary Planeswalker — Tezzeret card from Mirrodin Besieged (MBS), collector number 97. Current market price: $4.12 (foil $20.62), TCGplayer market prices via Scryfall.
+1: Look at the top five cards of your library. You may reveal an artifact card from among them and put it into your hand. Put the rest on the bottom of your library in any order. −1: Target artifact becomes an artifact creature with base power and toughness 5/5. −4: Target player loses X life and you gain X life, where X is twice the number of artifacts you control.