Members of The Lost are not considered a faction as they include various members of different factions from the galaxy, and even across the universe. The Losts came to the Twisted Clouds via different means carrying different goals. Some found their place here, some were just passing by.
They possess their own distinct characteristics and skill sets that can create unexpected outcomes when combined with other factions in battle.
"The Dragons called them The Losts, Dragons give names to everything. So we call them The Losts. But make no mistake, they are rarely lost and in battles they rarely lose."