Is Mazu a Buddha or not? How about worshipping the city god?

Mazu is not a Buddha. Is a real person in history. But there is a legend that Mazu is the incarnation of Guanyin Bodhisattva.

Mazu, formerly known as Moline, is called Moline Niang in the world. She was born in Meizhou Island, Putian County, Qingyuan Army in the early Song Dynasty. She was born in the first year of Stegosaurus in the Northern Song Dynasty. On March 23, 960, Mazu was a highly respected and outstanding woman in the Song Dynasty.

Born in power, teenagers are eager for Taoism, good at divination, good at medical skills and solving worries for the people; As an adult, I decided to give to all beings and never marry. My parents finally obeyed her wishes, which enabled her to devote herself to charity. Because of her intensive study of medicine, she often treats people and teaches people to prevent diseases and eliminate disasters, which has won everyone's admiration and respect, and people all praise her advantages. Maureen has always been a calm and helpful person. Solve problems for neighbors and villagers without asking for returns, and often guide people to avoid disasters and prevent shipwrecks.

Born in power, teenagers are eager for Taoism, good at divination, good at medical skills and solving worries for the people; As an adult Mazu, these characteristics are even more prominent. She is determined to give alms to all beings and never marry. Her parents finally obeyed her wishes, enabling her to devote herself to charity. Because of her intensive study of medicine, she often treats people and teaches people to prevent diseases and eliminate disasters, which has won everyone's admiration and respect, and people all praise her advantages. Maureen has always been a calm and helpful person. Solve problems for neighbors and villagers without asking for returns, and often guide people to avoid disasters and prevent shipwrecks.