Cheapest priced copy (Secrets of Strixhaven Commander): $1.49 at Card Kingdom, near mint, their price list as of .
Priest of Forgotten Gods 
Creature — Human Cleric · 1/2 · Rare · Secret Lair Drop · #2006
{T}, Sacrifice two other creatures: Any number of target players each lose 2 life and sacrifice a creature of their choice. You add {B}{B} and draw a card. (Activate only as an instant.)
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
7 printings · $1.49 to $7.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Foundations Jumpstart | 478 | Rare | $1.79 | — |
| Ravnica Allegiance Promos | 83p | Rare | $1.99 | $7.99 |
| Ravnica Allegiance Promos | 83s | Rare | — | $4.99 |
| Ravnica Allegiance | 83 | Rare | $1.79Out of stock | $3.49 |
| Ravnica Remastered | 90 | Rare | $1.79 | $3.49 |
| Secret Lair Drop | 2006 | Rare | $5.49 | $6.99 |
| Secrets of Strixhaven Commander | 225 | Rare | $1.49 | — |
3 rulings from Wizards of the Coast
- 25 January 2019You can activate the ability of Priest of Forgotten Gods without choosing any targets if you wish. You'll still add {B}{B} and draw a card.
- 25 January 2019Because it may have targets, the ability of Priest of Forgotten Gods isn't a mana ability. It uses the stack and can be responded to, even if no targets were chosen.
- 25 January 2019You may target players who can't sacrifice a creature. Those players still lose 2 life.