Cheapest priced copy (Commander Legends: Battle for Baldur's Gate): $0.49 at Card Kingdom, near mint, their price list as of .
Galepowder Mage 
Creature — Kithkin Wizard · 3/3 · Rare · Lorwyn · #15
Flying
Whenever this creature attacks, exile another target creature. Return that card to the battlefield under its owner's control at the beginning of the next end step.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
3 printings · $0.49 to $4.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Legends: Battle for Baldur's Gate | 694 | Rare | $0.49 | — |
| Duel Decks: Venser vs. Koth | 12 | Rare | $0.69 | — |
| Lorwyn | 15 | Rare | $1.29 | $4.49 |
3 rulings from Wizards of the Coast
- 1 October 2007Galepowder Mage's ability can target a creature controlled by any player. It's not optional.
- 1 October 2007If Galepowder Mage is the only creature on the battlefield when it attacks, its ability has no effect.
- 1 October 2007The exiled card will be returned to the battlefield at the beginning of the end step even if Galepowder Mage is no longer on the battlefield at that time.