Realizing his predicament, Jacob decided to try another method to keep himself from exhausting. He begins to use the magic gem to absorb the energy into his body and then again starts to swim.
Although it was working, it was mentally exhausting. But he had no choice but to persevere since stopping meant going back again and remaining trapped in the ocean forever.
After swimming for another ten miles, Jacob suddenly felt the gravity begin to lessen bit by bit, which meant he was approaching the surface albeit slowly, but he was getting there.
Many hours passed, and at some point, Jacob felt like he might fall asleep any moment because of the mental exhaustion. With bloodshot eyes, he continued to persevere, and the G-force was already lessened by half, so his speed was also getting faster.