There is already a book of Yoruba religion. Ifa books has been written and well documented, not knowing is the ignorance on the host part and a testament to the decay and rot
There is nothing like Oba in Lagos. Oba mean Emperor come to Benin and see numerous kings under Oba (emperor) of Benin. Benin is still an empire despite being called kingdom there are still numerous kingdom now called dukedoms still under the Oba of Benin and he is still making new kings and kingdoms in Benin empire.