One of my favorite video games is called Skylanders: Spyro's Adventure.
It is basicaly about a portal master(you) using the Skylanders to get all eight of the Eternal sources. These sources are Magic, Earth, Water, Fire, Teck, Undead, Air, and Life. There are different parts for a machine called The Core of Light to harness the Eternal sources so you can rebuild The Core of Light. The Core of Light's job is to keep the darkness at the outskirts of Skylands. After that you infltrat Kaos's castle shaped fortress. In the fortress you'll aventally have to fight a "hy-dra" and Kaos in a nother machine and the the the game is bacily over.:)