Cheapest priced copy (Adventures in the Forgotten Realms): $0.35 at Card Kingdom, near mint, their price list as of .
Monk of the Open Hand 
Creature — Elf Monk · 1/1 · Uncommon · Adventures in the Forgotten Realms · #25
Flurry of Blows — Whenever you cast your second spell each turn, put a +1/+1 counter on this creature.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
1 printing · $0.35 to $0.79 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Adventures in the Forgotten Realms | 25 | Uncommon | $0.35 | $0.79 |
2 rulings from Wizards of the Coast
- 23 July 2021Monk of the Open Hand doesn't need to have been on the battlefield as the first spell was cast. For example, if Monk of the Open Hand is the first spell you cast, and then you cast another spell after the Monk resolved, that spell would cause the Flurry of Blows ability to trigger.
- 23 July 2021If Monk of the Open Hand is the second spell you cast in a turn, spells you cast after that point in the same turn will not cause the Flurry of Blows ability to trigger.