Cheapest priced copy (Theros Beyond Death Promos): $6.99 at Card Kingdom, near mint, their price list as of .
Nyx Lotus 
Legendary Artifact · Rare · Theros Beyond Death Promos · #235p
Nyx Lotus enters tapped.
{T}: Choose a color. Add an amount of mana of that color equal to your devotion to that color. (Your devotion to a color is the number of mana symbols of that color in the mana costs of permanents you control.)
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
5 printings · $6.99 to $34.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Theros Beyond Death Promos | 235★ | Rare | — | $8.49 |
| Theros Beyond Death Promos | 235p | Rare | $6.99 | $8.99 |
| Theros Beyond Death Promos | 235s | Rare | — | $8.99 |
| Theros Beyond Death | 235 | Rare | $6.99 | $7.99 |
| Theros Beyond Death | 344 | Rare | $9.99 | $34.99 |
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 2020Mana symbols in the text boxes of permanents you control don’t count toward your devotion to any color.
- 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 2020Nyx Lotus’s second ability is a mana ability. It doesn’t use the stack and can’t be responded to.