Classification: CLASSIFIED
The Chaos Court studied fusion techniques combining different magical systems. An experiment on the fourth sublevel went wrong. The sublevel was sealed from inside. Shou Cang Dian official history says demon abyss fissure. This is a lie.
Three keys. Three holders: Yunzhong Jun, Tianjizi, Youtan.
Traces: A bloodstained note (There is no turning back from step three), a rune-carved stone (runes unknown to any formation system), a disappeared fragment of the Shattered Star Disk, a black stone disc (Eastern forces are searching for it), a sealed letter (Do not let them open the fourth level).