"The second reward is still the card in everyone's hands. With this card, you all can obtain Level 1 authority in Sky Mechanical City."
With Level 1 authority, Sky Mechanical City will offer various benefits. For example, you can fly at low altitudes to a limited extent. Or, for some shops with entry restrictions, like the Nail Alchemy House which only Alchemists can enter, you can bypass these restrictions with Level 1 authority.
Level 1 authority is equivalent to being a semi-permanent citizen of Sky Mechanical City.
For wandering Wizards, it is actually a pretty good choice. However, for those who are part of a Witcher Organization, this reward is just the icing on the cake.
Among those who entered the top hundred, wandering Wizards are few and far between. In the top ten, only Asaz is considered a wandering Wizard.
