That's a fine spoiler.

Of course it doesn't have to make sense .

The inclement sun shone on his head. The wind as hot as the heat of a bonfire struck his face and lifted thick clouds of dust that limited his vision. Even so, Booker walked without slowing his pace, even as his feet sank into the burning sand of the desert. He had already lost count of the hours he had been fighting against the elements of that place, wherever he fixed his sight, only dune after dune were the only things he could saw.

"Something bothers him."

"Or maybe he's afraid"

"That can be a plausible explanation"

"Still, he needs to keep pushing through."

In one of the towers, seated in the shade of a large palm tree, Seraphy closed her eyes and the air around her was filled with tiny electric shocks, in front of her, a small portal opened from which came a faint purple haze.

Almost here folks... almost here...