Cheapest priced copy (Journey into Nyx): $0.99 at Card Kingdom, near mint, their price list as of .
Prophetic Flamespeaker 
Creature — Human Shaman · 1/3 · Mythic · Journey into Nyx · #106
Double strike, trample
Whenever this creature deals combat damage to a player, exile the top card of your library. You may play it this turn.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
1 printing · $0.99 to $1.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Journey into Nyx | 106 | Mythic | $0.99 | $1.99 |
3 rulings from Wizards of the Coast
- 26 April 2014If Prophetic Flamespeaker deals combat damage to a player multiple times in a turn (if it wasn't blocked, for example), its triggered ability will trigger each time.
- 26 April 2014The card is exiled face up. Playing it follows the normal rules for playing that card. You must pay its costs, and you must follow all applicable timing rules. For example, if it's a creature card, you can cast it only during your main phase while the stack is empty.
- 26 April 2014If you exile a land card, you may play that land only if you have any available land plays. Normally, this means you can play the land only if you haven't played a land yet that turn.