Ottomoon is an alleged patron god of the Certain people. However, his existence has been fabricated by the Fat Free Republic of Fat Nation in a severe misunderstanding of Certain culture.

According to Fat Free Republic, Ottomoon is the Moon God. As the Slam Gods created the Sun, and Buddha created monks, Ottomoon created nothing and was entirely worthless. Ottomoon's appearance is unknown (as it doesn't exist) but the star and crescent is usually used to represent him and by extension, the Certain religion falsely. The Certain people worship the Slam Gods.

The misunderstanding arises from when Certain Country used the star and crescent as its flag in its more imperial days. In this matter, the symbol was entirely nationalistic rather than religious. When Crashbarzanes reformed the government into a theocracy, he replaced the flag with a blank green flag whose true form was only revealed in X-ray, a hidden insignia of a flexing arm doused in oil and gold.

Some say that the misunderstanding is deliberate because the Fat Free Republic is simply terrible. Similar terms coined by the Fat Free Republic include: FARTNATION and Carbombya.