FOILCheapest priced copy (Tarkir: Dragonstorm Promos): $0.49 at Card Kingdom, near mint, their price list as of .
Sidisi, Regent of the Mire 
Legendary Creature — Zombie Snake Warlock · 1/3 · Rare · Tarkir: Dragonstorm Promos · #92s
{T}, Sacrifice a creature you control with mana value X other than Sidisi: Return target creature card with mana value X plus 1 from your graveyard to the battlefield. Activate only as a sorcery.
Legal inCommanderBrawlStandardPioneerModernLegacyVintage
Not legal inPauper
4 printings · $0.49 to $0.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Tarkir: Dragonstorm Promos | 92p | Rare | $0.49 | $0.49 |
| Tarkir: Dragonstorm Promos | 92s | Rare | — | $0.69 |
| Tarkir: Dragonstorm | 92 | Rare | $0.49 | $0.49 |
| Tarkir: Dragonstorm | 341 | Rare | $0.49 | $0.99 |
One ruling from Wizards of the Coast
- 4 April 2025If a creature on the battlefield or a creature card in a graveyard has {X} in its mana cost, X is 0 for the purpose of determining its mana value.