24 Jan 2020
Only 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 Jan 2020
If 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 Jan 2020
If an Aura can't be attached to a creature you control, you can't return it to the battlefield.
24 Jan 2020
Storm Herald itself is among the creatures that may be enchanted by the returning Auras.