After a long search through the swamp, Geralt finds a cloven Salamandra Berengar and Geralt work together briefly, before Berengar explains why he left Kaer Morhen. He voices his disdain for the Witchers, whom he holds responsible for denying him a normal life. Later, on Black Tern Island, Berengar confronts Geralt with the intention of challenging him to a duel, forcing Geralt to choose once again, his next course of action.
If he spares Berengar, then Geralt will have an ally to aid in the final battle with Azar Javed. If he duels with Berengar (as Geralt tells Berengar, just before the fight), only one can come out alive and Geralt prevails. This leaves Geralt with Berengar's remaining belongings, which include a powerful medallion, so powerful in fact, that Azar Javed can not fail to notice it in the final battle.
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