Cheapest priced copy (Commander Anthology): $7.49 at Card Kingdom, near mint, their price list as of .
Dread Cacodemon 
Creature — Demon · 8/8 · Rare · Commander Anthology · #55
When this creature enters, if you cast it from your hand, destroy all creatures your opponents control, then tap all other creatures you control.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $7.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Anthology | 55 | Rare | $7.49 | — |
| Commander 2011 | 79 | Rare | $7.49 | — |
2 rulings from Wizards of the Coast
- 22 September 2011If you put Dread Cacodemon directly onto the battlefield from your hand, perhaps because of Kaalia of the Vast’s ability, its ability won’t trigger.
- 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.