Cheapest priced copy (Phyrexia: All Will Be One): $0.49 at Card Kingdom, near mint, their price list as of .
The Filigree Sylex 
Legendary Artifact · Rare · Phyrexia: All Will Be One · #394
{T}: Put an oil counter on The Filigree Sylex.
{T}, Sacrifice The Filigree Sylex: Destroy each nonland permanent with mana value equal to the number of oil counters on The Filigree Sylex.
{T}, Remove ten oil counters from among permanents you control and sacrifice The Filigree Sylex: It deals 10 damage to any target.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
4 printings · $0.49 to $1.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Phyrexia: All Will Be One | 227 | Rare | $0.49 | $0.49 |
| Phyrexia: All Will Be One | 394 | Rare | $0.59 | $0.49 |
| Phyrexia: All Will Be One Promos | 227p | Rare | $0.49 | $0.49 |
| Phyrexia: All Will Be One Promos | 227s | Rare | — | $1.99 |
One ruling from Wizards of the Coast
- 4 February 2023If a permanent has {X} in its mana cost, X is 0 when determining its mana value.