Cheapest priced copy (Jumpstart): $0.35 at Card Kingdom, near mint, their price list as of .
Elemental Uprising 
Instant · Common · Jumpstart · #390
Target land you control becomes a 4/4 Elemental creature with haste until end of turn. It's still a land. It must be blocked this turn if able.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
3 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Jumpstart | 390 | Common | $0.35 | — |
| Oath of the Gatewatch | 130 | Common | $0.35 | $0.49 |
| The List | OGW-130 | Common | $0.35 | — |
2 rulings from Wizards of the Coast
- 22 January 2016If the resulting creature attacks, the defending player must assign at least one blocker to it during the declare blockers step if that player controls any creatures that could block it.
- 22 January 2016You may target a land that’s already a creature. For example, if you target a land that’s also a 0/0 creature and has three +1/+1 counters on it, the resulting land creature will be 7/7.