Vivien, Monsters' Advocate

Legendary Planeswalker — Vivien{3}{G}{G}

You may look at the top card of your library any time. You may cast creature spells from the top of your library. +1: Create a 3/3 green Beast creature token. Put your choice of a reach counter, a vigilance counter, or a trample counter on it. −2: When you next cast a creature spell this turn, search your library for a creature card with lesser mana value, put it onto the battlefield, then shuffle.

Colour identity Green

In short

Vivien, Monsters' Advocate has 4 listed printings; the most valuable is the Prerelease printing from PIKO at US$5.74 on TCGplayer's market price. Prices below are the cheapest in-stock listing in the United States.