You gain resistance to fire damage.
Whenever you gain an aethari trait, you can also choose from the following:
Whenever you take type damage from a level 1 spell or higher, you gain a number of temporary hit points equal to your training die that last until the start of your next turn.
You have immunity to fire damage.
You have damage threshold to fire damage equal to your proficiency bonus.
You gain a gliding speed equal to your walking speed.
When you take the Spellcast action with a level 1 spell or higher that deals damage, you can replace the spell's damage type with fire damage.
You gain an Aetheri Subrace option, choosing from the list in the Subrace column in the Aetheri Subrace table. The option you choose grants you resistance to one or more damage types, a special speed equal to your walking speed, and inheritance of one spell at level 1, 3, and 5, choosing Intelligence, Wisdom, or Charisma as the spellcasting ability for these spells.