Cheapest priced copy (Dominaria): $6.49 at Card Kingdom, near mint, their price list as of .
Karn, Scion of Urza 
Legendary Planeswalker — Karn · Mythic · Dominaria · #1
+1: Reveal the top two cards of your library. An opponent chooses one of them. Put that card into your hand and exile the other with a silver counter on it.
−1: Put a card you own with a silver counter on it from exile into your hand.
−2: Create a 0/0 colorless Construct artifact creature token with "This token gets +1/+1 for each artifact you control."
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
6 printings · $6.49 to $18.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Dominaria | 1 | Mythic | $6.49 | $9.99 |
| Mythic Edition | RA1 | Mythic | — | $17.99 |
| Dominaria Promos | 1p | Mythic | $9.49 | $13.99 |
| Dominaria Promos | 1s | Mythic | — | $18.99 |
| Secret Lair Drop | 1419 | Mythic | $6.99 | — |
| Secret Lair Drop | 1419★ | Mythic | — | $7.49 |
2 rulings from Wizards of the Coast
- 27 April 2018A token created by Karn's last ability will count itself, so it'll be at least 1/1.
- 27 April 2018Karn is colorless but not an artifact. The Construct tokens created by Karn's last ability don't count Karn.