Cheapest priced copy (Bloomburrow): $0.35 at Card Kingdom, near mint, their price list as of .
Lightshell Duo 
Creature — Rat Otter · 3/4 · Common · Foundations · #157
Prowess (Whenever you cast a noncreature spell, this creature gets +1/+1 until end of turn.)
When this creature enters, surveil 2. (Look at the top two cards of your library, then put any number of them into your graveyard and the rest on top of your library in any order.)
Legal inCommanderBrawlStandardPioneerModernLegacyVintagePauper
2 printings · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Bloomburrow | 56 | Common | $0.35 | $0.49 |
| Foundations | 157 | Common | $0.35 | $0.49 |