What does Marlow prophesize he will meet with in the months ahead?

Marlow prophesizes that he will encounter more darkness and brutality in the months ahead, symbolized by the ominous and unsettling presence of Kurtz in the heart of Africa. This premonition suggests that Marlow's journey into the unknown will lead him to confront his own inner demons and test his moral compass amidst the harsh realities of colonial exploitation.