This sea is a strange and vast body of water that protects Quan Chi's other fortress, which is also known as the Pyramid of Shinnok, and the only way to cross it is the gigantic and cryptic stone bridge known as the Bridge of Immortality (named after the Sea of Immortality), which is heavily guarded by the Keepers. The Bridge itself, like the Pyramid of Shinnok, was built as the remainder of the old battleground, reminiscing the fallen Elder God's battle with previous enemies milliennia ago.