Cheapest priced copy (Mercadian Masques): $0.35 at Card Kingdom, near mint, their price list as of .
Cavern Crawler 
Creature — Insect · 0/3 · Common · Mercadian Masques · #181
Mountainwalk (This creature can't be blocked as long as defending player controls a Mountain.)
{R}: This creature gets +1/-1 until end of turn.
Legal inCommanderLegacyVintagePauper
Not legal inBrawlStandardPioneerModern
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Mercadian Masques | 181 | Common | $0.35 | $0.49 |