Cheapest priced copy (Phyrexia: All Will Be One): $0.79 at Card Kingdom, near mint, their price list as of .
Serum Sovereign 
Creature — Phyrexian Sphinx · 4/4 · Rare · Phyrexia: All Will Be One · #405
Flying
Whenever you cast a noncreature spell, put an oil counter on this creature.
{U}, Remove an oil counter from this creature: Draw a card, then scry 2.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
2 printings · $0.79 to $1.29 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Phyrexia: All Will Be One | 405 | Rare | $0.79 | $0.99Out of stock |
| Phyrexia: All Will Be One | 410 | Rare | $1.29 | — |
One ruling from Wizards of the Coast
- 4 February 2023Removing an oil counter is part of the cost to activate Serum Sovereign's last ability. Players can't respond with a spell or ability that removes counters to prevent you from drawing a card and scrying 2.