Cheapest priced copy (Commander 2011): $3.99 at Card Kingdom, near mint, their price list as of .
Trench Gorger 
Creature — Leviathan · 6/6 · Rare · Commander 2011 · #65
Trample
When this creature enters, you may search your library for any number of land cards, exile them, then shuffle. If you do, this creature has base power and base toughness each equal to the number of cards exiled this way.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $3.99 to $5.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2011 | 65 | Rare | $3.99 | — |
| The List | CMD-65 | Rare | $5.49 | — |
4 rulings from Wizards of the Coast
- 22 September 2011While Trench Gorger’s ability is on the stack, it’s on the battlefield as a 6/6.
- 22 September 2011If Trench Gorger leaves the battlefield before its triggered ability resolves, you may still search your library.
- 22 September 2011After the ability resolves, Trench Gorger’s power and toughness won’t change if one of the exiled cards leaves exile.
- 22 September 2011If you choose not to search, Trench Gorger will simply be 6/6.