Cheapest priced copy (Commander 2014): $1.99 at Card Kingdom, near mint, their price list as of .
Angel of the Dire Hour 
Creature — Angel · 5/4 · Rare · Jumpstart · #85
Flash
Flying
When this creature enters, if you cast it from your hand, exile all attacking creatures.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
3 printings · $1.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander 2014 | 1 | Rare | $1.99 | — |
| Jumpstart | 85 | Rare | $1.99 | — |
| The List | C14-1 | Rare | $1.99 | — |
3 rulings from Wizards of the Coast
- 7 November 2014If you cast Angel of the Dire Hour outside of combat, its triggered ability will trigger but have no effect.
- 7 November 2014If a spell or ability instructs you to put Angel of the Dire Hour onto the battlefield from your hand, that means you won’t have cast it, so its triggered ability won’t trigger.
- 7 November 2014Creatures that were declared as attackers or entered the battlefield attacking continue to be attacking creatures until the combat phase ends. It’s possible to exile all attacking creatures after they’ve dealt combat damage if you cast Angel of the Dire Hour during the combat damage step or end of combat step.