The fourth manvantara was called Tamas – named after Tamas Manu, who also had ten sons like his predecessor.
The names of his sons were – Akalmash, Tapodhanva, Tapomool, Tapodhan, Taporashi, Tapasya, Sutapasya, Parantap, Tapobhagi and Tapoyogi. Kavi, Prithu, Agni, Akapi, Kapi, Janya and Dhama were the Saptarishis of this manvantar, while Sadhyagana was the prominent deity.
Each manvantara is ruled over by a Manu. In the present kalpa, six manvantaras have already passed and the names of the six Manus who ruled were Svayambhuva, Svarochisha, Uttama, Tamasa, Raivata and Chakshusha. The name of the seventh Manu, who rules over the seventh manvantara of the present kalpa, is Vaivasvata.
The titles of the seven great sages (saptarshi) as well as the tile of Indra change from manvantara to manvantara. The gods also change.
Was Shiv Puran written specially for Tamas Manvantar, where Lord Shiv becomes greater than Lord Vishnu
Yes! Precisely! This is where the notion of “contradiction” becomes destroyed.