Cheapest priced copy (Wilds of Eldraine): $0.69 at Card Kingdom, near mint, their price list as of .
Wildwood Mentor 
Creature — Treefolk · 1/1 · Rare · Wilds of Eldraine · #322
Whenever a token you control enters, put a +1/+1 counter on this creature.
Whenever this creature attacks, another target attacking creature gets +X/+X until end of turn, where X is this creature's power.
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
2 printings · $0.69 to $1.29 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Wilds of Eldraine | 322 | Rare | $0.69 | $0.99 |
| Wilds of Eldraine | 374 | Rare | $1.29 | — |