Cheapest priced copy (The Brothers' War Commander): $0.49 at Card Kingdom, near mint, their price list as of .
Kayla's Music Box 
Legendary Artifact · Rare · The Brothers' War Commander · #15
{W}, {T}: Look at the top card of your library, then exile it face down. (You may look at it any time.)
{T}: Until end of turn, you may play cards you own exiled with Kayla's Music Box.
Legal inCommanderLegacyVintage
Not legal inBrawlStandardPioneerModernPauper
2 printings · $0.49 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| The Brothers' War Commander | 15 | Rare | $0.49 | — |
| The Brothers' War Commander | 62 | Rare | $0.49 | — |
One ruling from Wizards of the Coast
- 14 October 2022No other player may look at the face-down cards you own exiled with Kayla’s Music Box, even if another player takes control of it.