Cheapest priced copy (The Lost Caverns of Ixalan Commander): $0.69 at Card Kingdom, near mint, their price list as of .
Champion of Dusk 
Creature — Vampire Knight · 4/4 · Rare · Rivals of Ixalan · #64
When this creature enters, you draw X cards and you lose X life, where X is the number of Vampires you control.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
4 printings · $0.69 to $6.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| The Lost Caverns of Ixalan Commander | 188 | Rare | $0.69 | — |
| Rivals of Ixalan Promos | 64s | Rare | — | $6.49 |
| Rivals of Ixalan | 64 | Rare | $0.69 | $3.49 |
| Crimson Vow Commander | 124 | Rare | $0.69 | — |
One ruling from Wizards of the Coast
- 19 January 2018The number of Vampires you control is counted only as Champion of Dusk's ability resolves. If Champion of Dusk is still on the battlefield, it'll count itself.