A character who's heratidge may or may not grant them some sort of special ability or magic power, it may just impress people
Name Space: Main
Page Type: Trope
The protagonist is in a corner surrounded by thugs or goblins or pirates: buts its fine their alien dna means that they are strong enough to take care of the situation. To clarify they aren't an alien or half alien but somewhere way back in their lineage there is an extraterrestrial, it also doesn't necessarily have to be aliens it could be dragons, demigods or in a the magic went away situation they may be descended from wizards.
Occasionally they may not even have special powers however their dna does get them extra respect from those in the know and they'll probably get a little nod from the wise old man or some ancient order will attempt to hire them/hunt them down.
Bonus points if they and/or their ancestor is the chosen one.