The Sikh Guru who called himself the `Sachcha Badshah` is Guru Tegh Bahadur, as mentioned in option 3. The term `Sachcha Badshah` translates to `True Emperor` in English. Guru Tegh Bahadur, who was the ninth Sikh Guru, used this title to signify his commitment to truth and justice. He believed in upholding the principles of righteousness and standing up against injustice. Guru Tegh Bahadur`s self-identification as the `Sachcha Badshah` reflects his role as a spiritual leader and his dedication to protecting the rights and faith of his people. It is important to note that the other options listed do not accurately represent the Sikh Guru who called himself the `Sachcha Badshah`.