Bahamut Senki is a turn-based war strategy game with fantastical elements, developed and published by Sega themselves exclusively for their Sega Mega Drive console. It was never localized into English. It was eventually ported to the Japanese Wii Shop's Virtual Console in 2007.
The world of Bahumut is divided into eight powerful countries, four of which are ruled by humans or human-like creatures, while the other four are ruled by evil forces. These countries constantly wage war against one another trying to dominate and destroy the others. It's the player's job to choose which country to control and make it the most powerful country in all of Bahumut.
At the beginning of each turn, the player controls their leader and takes certain actions such as: recruit soldiers, declare war, engage in diplomatic talks, et cetera. In battles they can control several units of soldiers or can summon magical creatures to assist them in battle.