Cheapest priced copy (Throne of Eldraine): $2.99 at Card Kingdom, near mint, their price list as of .
Deafening Silence 
Enchantment · Uncommon · Mystery Booster 2 · #9
Each player can't cast more than one noncreature spell each turn.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
4 printings · $2.99 to $19.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Throne of Eldraine | 10 | Uncommon | $2.99 | $5.99 |
| Mystery Booster 2 | 9 | Uncommon | $2.99 | — |
| Secret Lair Drop | 1219 | Rare | $13.99 | $19.99 |
| Special Guests | 120 | Mythic | $8.99 | $14.99 |
3 rulings from Wizards of the Coast
- 4 October 2019Deafening Silence will look at the entire turn to see if a player has cast a noncreature spell yet that turn, even if Deafening Silence wasn't on the battlefield when that spell was cast. Notably, you can't cast Deafening Silence and then cast another noncreature spell that turn.
- 4 October 2019Players may cast any number of creature spells plus one noncreature spell each turn.
- 4 October 2019If you cast a noncreature spell that was countered, you can't cast another noncreature spell that turn.