Life and Death Exchange: I Got an Extra Fiancé Inexplicably

Mermaid+House Seizing+Sweet Pet+Nurture Legend has it that above the West Sea, among the clouds and mist, stands a cloud tower. If you want to climb this tower, you must give up one of your most important things. Under the severe pollution of nuclear wastewater, marine life began to mutate bizarrely and attack other creatures inexplicably. In a desperate situation, the mermaid princess decided to lead the race to find the legendary Xihaiyun Tower in search of hope. But there are many dangers along the way, how should they find it? How to climb the stairs? In the end, what situation will they face? ? ?