Cheapest priced copy (Foundations): $0.35 at Card Kingdom, near mint, their price list as of .
Goblin Boarders 
Creature — Goblin Pirate · 3/2 · Common · Foundations · #87
Raid — This creature enters with a +1/+1 counter on it if you attacked this turn.
Legal inCommanderBrawlStandardPioneerModernLegacyVintagePauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Foundations | 87 | Common | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 8 November 2024Raid abilities care only that you attacked with a creature. It doesn't matter how many creatures you attacked with or which player, planeswalker, or battle those creatures attacked.
- 8 November 2024Raid abilities evaluate the entire turn to see if you attacked with a creature. That creature doesn't have to still be on the battlefield. Similarly, the player, planeswalker, or battle it attacked doesn't have to still be in the game or on the battlefield.