Cheapest priced copy (Foundations): $0.35 at Card Kingdom, near mint, their price list as of .
Billowing Shriekmass 
Creature — Spirit · 2/3 · Uncommon · Foundations · #56
Flying
When this creature enters, mill three cards. (Put the top three cards of your library into your graveyard.)
Threshold — This creature gets +2/+1 as long as there are seven or more cards in your graveyard.
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
1 printing · $0.35 to $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Foundations | 56 | Uncommon | $0.35 | $0.49 |
One ruling from Wizards of the Coast
- 8 November 2024Because damage remains marked on a creature until the damage is removed as the turn ends, nonlethal damage dealt to Billowing Shriekmass may become lethal if the number of cards in your graveyard falls below seven.