The Rebbe concluded the first berakhah with the words “hazon be-rachamav es ha-kol.” This was the minhag of the Baal Shem Tov and his family. Most Breslovers follow this custom today.
(Oral tradition. Cf. Likkutei MaHaRiCH, Seder Birkhas ha-Mazon, citing Tola’as Yaakov. This was also the nusach of the Manistricher Chassidim in Uman; Rabbi Avraham Yehoshua Rabinowitz, Ehrkei Yehoshua, Kuntres Perach Shoshanim 40. Some old Yerushalayimer Chassidic families have this custom, too)