Cheapest priced copy (Aetherdrift): $2.49 at Card Kingdom, near mint, their price list as of .
Riverchurn Monument 
Artifact · Rare · Aetherdrift · #57
{1}, {T}: Any number of target players each mill two cards. (Each of them puts the top two cards of their library into their graveyard.)
Exhaust — {2}{U}{U}, {T}: Any number of target players each mill cards equal to the number of cards in their graveyard. (Activate each exhaust ability only once.)
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
5 printings · $2.49 to $7.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Aetherdrift | 57 | Rare | $2.49 | $2.99 |
| Aetherdrift | 381 | Rare | $2.79 | $2.99 |
| Aetherdrift | 440 | Rare | — | $7.99 |
| Aetherdrift Promos | 57p | Rare | $2.79 | $3.49 |
| Aetherdrift Promos | 57s | Rare | — | $4.49 |
3 rulings from Wizards of the Coast
- 7 February 2025If an ability triggers whenever you activate an exhaust ability, that ability resolves before the exhaust ability resolves.
- 7 February 2025If an exhaust ability of a permanent is activated, and then that permanent leaves the battlefield and returns to the battlefield, it becomes a new object so its exhaust ability can be activated again.
- 7 February 2025Exhaust abilities can be activated any time you could normally activate an ability.