Cheapest priced copy (The List): $1.29 at Card Kingdom, near mint, their price list as of .
Gray Merchant of Asphodel 
Creature — Zombie · 2/4 · Uncommon · Theros Beyond Death · #99
When this creature enters, each opponent loses X life, where X is your devotion to black. You gain life equal to the life lost this way. (Each {B} in the mana costs of permanents you control counts toward your devotion to black.)
Legal inCommanderPioneerModernLegacyVintagePauper
Not legal inBrawlStandard
14 printings · $1.29 to $149.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2014 | 146 | Common | $1.79 | — |
| Duskmourn: House of Horror Commander | 142 | Uncommon | $2.29 | — |
| Foundations Commander | 105 | Uncommon | $1.49 | — |
| The List | C14-146 | Common | $1.29 | — |
| Starter Commander Decks | 80 | Uncommon | $1.49 | — |
| Secret Lair Countdown | 7 | Rare | $12.99 | $21.99 |
| Secret Lair Countdown | 34 | Rare | — | $109.99 |
| The Zeta Set | 43 | Common | — | — |
| The Zeta Set | 164 | Common | — | — |
| The Zeta Set | 285 | Common | — | — |
| Theros Beyond Death | 99 | Uncommon | $1.29 | $4.49 |
| Theros Beyond Death | 355 | Uncommon | $6.99 | $11.99 |
| Theros | 89 | Common | $1.49 | $14.99 |
| Time Spiral Remastered | 323 | Special | $8.99 | $149.99 |
6 rulings from Wizards of the Coast
- 24 January 2020If you put an Aura on an opponent's permanent, you still control the Aura, and mana symbols in its mana cost count towards your devotion.
- 24 January 2020Colorless and generic mana symbols ({C}, {0}, {1}, {2}, {X}, and so on) in mana costs of permanents you control don't count toward your devotion to any color.
- 24 January 2020If an activated ability or triggered ability has an effect that depends on your devotion to a color, you count the number of mana symbols of that color among the mana costs of permanents you control as the ability resolves. The permanent with that ability will be counted if it's still on the battlefield at that time.
- 24 January 2020Hybrid mana symbols, monocolored hybrid mana symbols, and Phyrexian mana symbols do count toward your devotion to their color(s).
- 24 January 2020Mana symbols in the text boxes of permanents you control don't count toward your devotion to any color.
- 19 March 2021The amount of life you gain is the total amount of life lost, not simply the value of X.