Cheapest priced copy (Archenemy: Nicol Bolas): $3.99 at Card Kingdom, near mint, their price list as of .
Nissa, Worldwaker 
Legendary Planeswalker — Nissa · Mythic · Magic 2015 · #187
+1: Target land you control becomes a 4/4 Elemental creature with trample. It's still a land.
+1: Untap up to four target Forests.
−7: Search your library for any number of basic land cards, put them onto the battlefield, then shuffle. Those lands become 4/4 Elemental creatures with trample. They're still lands.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
3 printings · $3.99 to $54.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Archenemy: Nicol Bolas | 68 | Mythic | $3.99 | — |
| Magic 2015 | 187 | Mythic | $4.99 | $15.99 |
| San Diego Comic-Con 2014 | 187 | Mythic | — | $54.99 |
2 rulings from Wizards of the Coast
- 18 July 2014The type-changing effects of the first and third abilities don’t have a duration. They last indefinitely.
- 18 July 2014If the land targeted by the first ability entered the battlefield this turn, it won’t be able to attack and its activated abilities with {T} in the cost (including its mana ability) can’t be activated (unless something gives it haste). The same is true for the lands put onto the battlefield with the third ability.