Career
Rabbi Leifer served as Grand Rabbi of Nadvirna (Nadwórna). Hasidim from all over Hungary and Romania would come to receive his blessings. An extraordinarily large number of his descendants became Hasidic rebbes, including many around the world today.
His teachings are collected in Gedulas Mordechai, Tiferes Mordechai, Aspaklarya Hameira, and Maamar Mordechai.
Rebbe Yitzchock Leifer of Stanislav
Rebbe Yisaschar Bertzi of Satmar
Rebbe Meir Rosenbaum of Kretchnif
Rebbe Aharon Moshe of Żołynia-Łańcut
Rebbe Yisroel Yaakov of Chust
Rebbe Yoseph Leifer of Niredhaz
Rebbitzen Leah Bina Igra of Zolynia (died childless)
Today, there are close to 100 Grand Rebbes who claim descendancy from Rebbe Mordechai of Nadvorna.