Cheapest priced copy (Innistrad: Double Feature): $0.35 at Card Kingdom, near mint, their price list as of .
Witness the Future 
Sorcery · Uncommon · Innistrad: Crimson Vow · #90
Target player shuffles up to four target cards from their graveyard into their library. You look at the top four cards of your library, then put one of those cards into your hand and the rest on the bottom of your library in a random order.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
2 printings · $0.35 to $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Innistrad: Double Feature | 357 | Uncommon | $0.35 | $0.79 |
| Innistrad: Crimson Vow | 90 | Uncommon | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 19 November 2021If you choose zero target cards or the cards are illegal targets as Witness the Future resolves, the target player will still shuffle their library.
- 19 November 2021If the player is an illegal target as Witness the Future resolves, the library won't be shuffled and any targeted cards remain in the graveyard.