Cheapest priced copy (Strixhaven: School of Mages): $0.35 at Card Kingdom, near mint, their price list as of .
Bayou Groff 
Creature — Plant Dog · 5/4 · Common · Strixhaven: School of Mages · #121
As an additional cost to cast this spell, sacrifice a creature or pay {3}.
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Strixhaven: School of Mages | 121 | Common | $0.35 | $0.49 |
2 rulings from Wizards of the Coast
- 16 April 2021Players can respond to Bayou Groff only after it’s been cast and all its costs have been paid. No one can try to destroy the creature you sacrificed to stop you from casting this spell or to make it cost more mana.
- 16 April 2021You must sacrifice exactly one creature or pay an extra {3} to cast this spell; you can’t cast it without paying one of those costs, and you can’t pay either multiple times.