Cheapest priced copy (Murders at Karlov Manor): $0.69 at Card Kingdom, near mint, their price list as of .
Extract a Confession 
Sorcery · Common · Murders at Karlov Manor · #84
As an additional cost to cast this spell, you may collect evidence 6. (Exile cards with total mana value 6 or greater from your graveyard.)
Each opponent sacrifices a creature of their choice. If evidence was collected, instead each opponent sacrifices a creature with the greatest power among creatures they control.
Legal inCommanderBrawlStandardPioneerModernLegacyVintagePauper
1 printing · $0.69 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Murders at Karlov Manor | 84 | Common | $0.69 | $0.99 |
4 rulings from Wizards of the Coast
- 2 February 2024If evidence was collected and an opponent has multiple creatures tied for the greatest power, that player chooses which one to sacrifice.
- 2 February 2024Once you've announced that you're casting a spell, players can't take actions until you've finished doing so. Notably, opponents can't try to remove cards from your graveyard to stop you from collecting evidence.
- 2 February 2024Starting with the next opponent in turn order (or, if you cast Extract a Confession on an opponent's turn, starting with the opponent whose turn it is) and proceeding in turn order, each opponent chooses a creature they control to sacrifice. Then those creatures are sacrificed at the same time.
- 2 February 2024If you can't exile enough cards to meet or exceed the required mana value, you can't choose to collect evidence at all.