1)
Who will come to Eretz ha'Tzvi"?
1.
Ibn Ezra: Melech ha'Tzafon i.e. Melech Constantine..
2)
Who will stumble?
1.
Malbim: Many eastern lands 1 will be too weak to stand against him.
1
The verse said only that he will come to Eretz ha'Tzvi (Eretz Yisrael)! (PF)
3)
Who will be saved from him?
1.
Ibn Ezra: Those who dwell where Edom, Mo'av and the head of Amon dwelled.
