Cheapest priced copy (Planeshift): $0.35 at Card Kingdom, near mint, their price list as of .
Amphibious Kavu 
Creature — Kavu · 2/2 · Common · Planeshift · #78
Whenever this creature blocks or becomes blocked by one or more blue and/or black creatures, this creature gets +3/+3 until end of turn.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern
1 printing · $0.35 to $1.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Planeshift | 78 | Common | $0.35 | $1.49 |
One ruling from Wizards of the Coast
- 4 October 2004The ability only triggers once per combat.