Cheapest priced copy (Reality Fracture Commander): $0.49 at Card Kingdom, near mint, their price list as of .
Proteus Staff 
Artifact · Rare · Mirrodin · #230
{2}{U}, {T}: Put target creature on the bottom of its owner's library. That creature's controller reveals cards from the top of their library until they reveal a creature card. The player puts that card onto the battlefield and the rest on the bottom of their library in any order. Activate only as a sorcery.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
3 printings · $0.49 to $39.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Reality Fracture Commander | 59 | Rare | $0.49 | — |
| Mystery Booster 2 | 140 | Rare | $1.29 | $1.29 |
| Mirrodin | 230 | Rare | $2.49 | $39.99 |