Cyrus is the leader of Team Galactic in the Sinnoh Region. He is quite emotionless and wants to create a universe without emotion or strife. He is the descendant of Cyllene
At Team Galactic's headquarters, thanks to the commanders taking action, he managed to escape with Azelf, Uxie and Mesprit still under his control. Before doing so, he revealed to Ash and his friends that he intended to control the Lake Trio with the Red Chain fragments and create a new world where he would reign as a god.
He later arrived at Mt. Coronet along with Mars, Saturn, Jupiter and Charon, and using the Spear Key and the Red Chain fragment on his glove, he revealed the entrance to Spear Pillar. Once in there, he took advantage of the Lake Trio's powers and the Adamant and Lustrous Orbs to summon the legendary Pokémon Dialga and Palkia. By further manipulating the powers of the Red Chain, he trapped both Pokémon and commanded them to create a new world. When the portal to the new dimension opened, he forbid any of his team members to enter it, because he didn't deem them worthy enough of the new world he wanted to create. Once the rings that enabled him to control the legendary Pokémon were destroyed by Ash and the others, though, the portal started to rapidly close. However, he managed to go through it, and vanished into the new universe when it completely closed.