The Godbox is an artifact that appears in Divinity: Original Sin. It's the only vessel capable of containing an immortal being, according to Zandalor.
At ancient days, a great evil called Void Dragon threatened Rivellon. Two great human warriors fought against the dragon and sealed it in this box. After then, two warriors volunteered as the Guardians of the Godbox and kept it closed for eternal times.
But one day, Astarte was allured by the Trife and distracted the Guardians. She opened the Godbox mistakenly, and the Void Dragon was set free. After then, Astarte had been fighting with the Void Dragon for ages but the power of the Void was growing bigger and bigger.
After the final battle, Astarte once again seals the Great Evil inside the Godbox and the Guardians lived happily ever after.