Cheapest priced copy (Duel Decks: Divine vs. Demonic): $0.99 at Card Kingdom, near mint, their price list as of .
Reiver Demon 
Creature — Demon · 6/6 · Rare · Mirrodin · #75
Flying
When this creature enters, if you cast it from your hand, destroy all nonartifact, nonblack creatures. They can't be regenerated.
Legal inCommanderModernLegacyVintage
Not legal inBrawlStandardPioneerPauper
5 printings · $0.99 to $10.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Anthology | 64 | Rare | $1.29 | — |
| Commander 2011 | 95 | Rare | $1.79 | — |
| Duel Decks: Divine vs. Demonic | 43 | Rare | $0.99 | — |
| Duel Decks Anthology: Divine vs. Demonic | 43 | Rare | $2.29 | — |
| Mirrodin | 75 | Rare | $1.29 | $10.99 |
One ruling from Wizards of the Coast
- 20 September 2013If a creature (such as Clone) enters the battlefield as a copy of this creature, the copy’s “enters-the-battlefield” ability will still trigger as long as you cast that creature spell from your hand.