Cheapest priced copy (Magic 2015): $0.69 at Card Kingdom, near mint, their price list as of .
Goblin Kaboomist 
Creature — Goblin Warrior · 1/2 · Rare · Magic 2015 · #144
At the beginning of your upkeep, create a colorless artifact token named Land Mine with "{R}, Sacrifice this token: This token deals 2 damage to target attacking creature without flying." Then flip a coin. If you lose the flip, this creature deals 2 damage to itself.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
2 printings · $0.69 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Magic 2015 | 144 | Rare | $0.69 | $0.79 |
| The List | M15-144 | Rare | — | $0.99 |
2 rulings from Wizards of the Coast
- 18 July 2014The Land Mine tokens have the ability even if Goblin Kaboomist blows himself up or otherwise leaves the battlefield.
- 18 July 2014You flip the coin after the Land Mine token is created, not after you sacrifice a Land Mine. The token is created even if you lose the flip.