The Travelers

Deep north beyond where most dare to tread, a group of cats forced from their homes in warmer, kinder places live. For hundreds of moons, they have lived on the distant ocean shores, far away from where they once called home. They've survived perilous winters, drought-filled summers, and disease after disease which threatened their clan, "The Travelers".
They say that the first seven who arrived to the new clan died and ascended to godhood, save one. They say that that the final of the seven, Lifetrotter, will be born again when the clan is in great danger.
And when a new prophecy is told, one that predicts Lifetrotter's reincarnation, one that claims said reincarnation will be the one to save The Travelers from a great evil-- a question arises.
What is this great evil they need to be saved from?