Ha van bennem kb 12,5% szerb vér, akkor van rá esélyem, hogy megkapjam a szerb állampolgárságot?

Ezen az úton biztosan nem...

Citizenship of the Republic of Serbia based on origin is acquired, under different conditions, by children if both or one parent is a national of the Republic of Serbia at the moment of the child's birth.

You should make sure to report in good time the child's birth to the relevant diplomatic or consular mission of the Republic of Serbia in order that its name may be entered in the register of citizens of the Republic of Serbia.

If your parents were nationals of the Republic of Serbia at the time of your birth, if you are of age, but under 23, and if, as a child, you were left without citizenship and were not registered, you should file an application to that effect with the relevant diplomatic or consular mission of the R. of Serbia.