Cheapest priced copy (Commander Legends): $0.99 at Card Kingdom, near mint, their price list as of .
Viscera Seer 
Creature — Vampire Wizard · 1/1 · Common · Magic 2011 · #120
Sacrifice a creature: Scry 1. (Look at the top card of your library. You may put that card on the bottom.)
Legal inCommanderModernLegacyVintagePauper
Not legal inBrawlStandardPioneer
9 printings · $0.99 to $24.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2013 | 99 | Common | $1.79 | — |
| Commander Legends | 158 | Common | $0.99 | $1.99 |
| Commander Legends | 658 | Common | $5.49 | $24.99 |
| The Lost Caverns of Ixalan Commander | 213 | Common | $1.29 | — |
| Magic 2011 | 120 | Common | $1.29 | $11.99 |
| The List | M11-120 | Common | — | $1.99 |
| Secret Lair Drop | VS | Common | — | — |
| Secrets of Strixhaven Commander | 229 | Common | $1.49 | — |
| Tarkir: Dragonstorm Commander | 199 | Common | $0.99Out of stock | — |
2 rulings from Wizards of the Coast
- 15 August 2010If you sacrifice an attacking or blocking creature during the declare blockers step, it won't deal combat damage. If you wait until the combat damage step, but that creature is dealt lethal damage, it'll be destroyed before you get a chance to sacrifice it.
- 15 August 2010You can sacrifice Viscera Seer to activate its own ability.