A summary of season one of Tensei shitara Slime Datta Ken with some extra content leading into season two.

Taking a break from his time as a teacher, the powerful slime Rimuru Tempest returns to his kingdom, eponymously named Tempest, just in time to begin negotiations with a nearby nation—the Kingdom of Eurazania. While the negotiations are anything but peaceful, they do end successfully, allowing Rimuru to return and finish teaching. When trying to again return to Tempest, this time permanently, Rimuru is stopped by a mysterious figure who is somehow able to constrain the many magical abilities he has at his disposal. In Tempest, the situation is even worse. A group of unknown humans has invaded the land and are assaulting its citizens, both influential and innocent. They are not just trying to bring harm either—they have the intent to kill. Can Rimuru overcome his powerful and dangerous foe and return to Tempest before it is too late?

The nation of Tempest is in a festive mood after successfully overcoming the surprise attack from the Falmuth Army and the Western Holy Church. Beyond the festivities lies a meeting between Tempest and its allies to decide the future of the Nation of Monsters. The aftermath of the Falmuth invasion, Milim Nava's suspicious behavior, and the disappearance of Demon Lord Carrion—the problems seem to keep on piling up. Rimuru Tempest, now awakened as a True Demon Lord, decides to go on the offensive against Clayman. With the fully revived Storm Dragon Veldora, Ultimate Skill Raphael, and other powerful comrades, the ruler of the Tempest is confident in taking down his enemies one by one until he can face the man pulling the strings.

Doraemon and its friends open a hole in the time and they're travel to the Country of Mayana, a lost Mayan civilization in the jungle. There, Nobita will know its perfect double, prince Thio, heir to the throne. Both will decide to interchange papers to try to save to the Country of Mayana of the claws of the infernal Ledina witch and her evil forces. (Source: ANN)