How to clear such a large water body?

Mo Qiang followed Mo Xifeng as the latter guided her to the ocean. The closer the two of them got to the ocean, the more Mo Qiang felt a sudden pressure rise in her heart. With infrared vision, she looked at Mo Xifeng before her eyes fell on the sea that was covered with mist that was even darker than it was before. 

Even though the two of them were still far away, Mo Qiang heard a loud churn before a wave washed over the shore causing the ground to shake and rumble. She looked down at her feet which were covered with dark violet liquid and her face twisted in disgust. 

" What is this??" She questioned as she pulled her feet back, only to find that the liquid that was sticking to her shoes was actually stuck in the liquid and she could not move her feet anymore.