Cheapest priced copy (Duel Decks: Merfolk vs. Goblins): $0.35 at Card Kingdom, near mint, their price list as of .
Tidal Warrior 
Creature — Merfolk Warrior · 1/1 · Common · Stronghold · #47
{T}: Target land becomes an Island until end of turn.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern
3 printings · $0.35 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Duel Decks: Merfolk vs. Goblins | 20 | Common | $0.35 | — |
| The List | DDT-20 | Common | $0.35 | — |
| Stronghold | 47 | Common | $0.35 | — |