While at Massawa, his brother Estêvão da Gama attempted to salvage something from this expedition by dispatching an expeditionary force under Cristóvão to assist the beleaguered Emperor of Ethiopia, Gelawdewos.

Four hundred Portuguese men-at-arms were selected, 70 of whom were also skilled artisans or engineers, and 130 slaves for this expedition, equipped with about 1000 arquebuses, an equal number of pikes and several bombards.

[5] The Portuguese reached Debarwa after a march of 11 days on 20 July, to learn that the rainy season (which Castanhoso, as well as the natives, referred to as "winter") made further travel impossible.

[6] Cristóvão would not allow his men to pass the months in idleness, employing them in constructing sledges for the bombards and in raiding nearby villages that had accepted Ahmed Gragn's rule.

As Queen Seble Wongel had feared, the events at Bacente alerted Ahmad that a hostile army had entered the area, and he marched north to confront it, meeting Gama at Jarte (which Pedro Paez identifies with Sahart, although Whiteway locates it in the Wajirat Mountains).

Whiteway identifies the Imam's refuge as a village named Wajarat,[16] while J. Spencer Trimingham places it in the Zobil mountains overlooking the Afar Depression.

[17] Gama marched after him as far as Lake Ashangi, where on the advice of Queen Seble Wongel, he made camp on a hill in Wofla as the rainy season started.

At some point late in the rains, Gama was approached by a Jew (possibly one of the Beta Israel), who told him of a mountain stronghold that Ahmad Gragn's followers controlled weakly (identified by Whiteway as Amba Sel).

[18] It was also at this time that Gama was accurately informed about the Emperor Gelawdewos's true strength: the Ethiopian monarch was living as an outlaw in the south, with only 60 to 70 men in his army.

[23] In the end Ahmad Gragn chopped off Gama's head and tossed it into a nearby spring, whose waters Castanhoso reported gained a reputation for giving "health to the sick".

Using the arms stockpiled at Debre Damo, the Portuguese were able to rearm themselves; with the promise of their ability, Gelawdewos was able to raise a new army, which met Ahmad Gragn at Wayna Daga.

While the sources differ on the exact details, most agree that Ahmad Gragn was killed by the men of Cristóvão da Gama to avenge their commander's death.