Cheapest priced copy (Theros Beyond Death Promos): $0.49 at Card Kingdom, near mint, their price list as of .
Storm Herald 
Creature — Human Shaman · 3/2 · Rare · Theros Beyond Death Promos · #156p
Haste
When this creature enters, return any number of Aura cards from your graveyard to the battlefield attached to creatures you control. Exile those Auras at the beginning of your next end step. If those Auras would leave the battlefield, exile them instead of putting them anywhere else.
Legal inCommanderPioneerModernLegacyVintage
Not legal inBrawlStandardPauper
4 printings · $0.49 to $1.99 at Card Kingdom
| Set | Number | Rarity | Card Kingdom | Foil |
|---|---|---|---|---|
| Theros Beyond Death Promos | 156p | Rare | $0.49 | $1.99 |
| Theros Beyond Death Promos | 156s | Rare | — | $1.29 |
| Theros Beyond Death | 156 | Rare | $0.49 | $0.49 |
| Theros Beyond Death | 321 | Rare | $0.49 | $1.99 |
4 rulings from Wizards of the Coast
- 24 January 2020Only Auras that were returned to the battlefield will be exiled at the beginning of your next end step. Any that you choose to leave in your graveyard will remain.
- 24 January 2020If an effect exiles an Aura returned this way, that effect exiles it, not Storm Herald's effect. If that effect returns the Aura to the battlefield, it won't be affected by Storm Herald's effect anymore.
- 24 January 2020If an Aura can't be attached to a creature you control, you can't return it to the battlefield.
- 24 January 2020Storm Herald itself is among the creatures that may be enchanted by the returning Auras.