Cheapest priced copy (Commander Masters): $0.79 at Card Kingdom, near mint, their price list as of .
Sarkhan the Masterless 
Legendary Planeswalker — Sarkhan · Rare · War of the Spark · #143
Whenever a creature attacks you or a planeswalker you control, each Dragon you control deals 1 damage to that creature.
+1: Until end of turn, each planeswalker you control becomes a 4/4 red Dragon creature and gains flying.
−3: Create a 4/4 red Dragon creature token with flying.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
6 printings · $0.79 to $12.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Commander Masters | 880 | Rare | $0.79 | — |
| War of the Spark Promos | 143s | Rare | — | $2.29Out of stock |
| War of the Spark Promos | 143s★ | Rare | — | $10.99 |
| Secret Lair Drop | 514 | Rare | — | $3.49 |
| War of the Spark | 143 | Rare | $0.79 | $1.49 |
| War of the Spark | 143★ | Rare | $1.29 | $12.99 |
2 rulings from Wizards of the Coast
- 3 May 2019A planeswalker that becomes a creature due to Sarkhan’s first loyalty ability can’t attack unless you’ve controlled it continuously since your turn began.
- 3 May 2019Once Sarkhan’s first loyalty ability has resolved, each planeswalker you control (including Sarkhan) is no longer a planeswalker for the rest of the turn. They don’t lose any loyalty counters or abilities, and you can still activate their loyalty abilities if you haven’t done so yet this turn. They don’t lose loyalty if they’re dealt damage while they’re not planeswalkers.