For our purpose, a Native is someone that was born with in the veil of Yurenth. People that are born outside the realm of Yurenth are called aliens, or rifters.
Natives have some special rules. Things like Yurenth Elves and Fey are vulnerable to certain metals.
When a Native of Yurenth leaves the veil of Yurenth, they will get the Brand of Yurenth. When they return the brand will disappear. Likewise when you are in Yurenth and you see the Brand you can assume the character is alien to Yurenth, and they got the brand when they entered the realm.