Lightning Tower First level
Back in the Tormented World, when Fruity was breaking through to the Sage stage, the final phase of the tribulation was something Yuying called the Tribulation Tower.
According to her, this tower was one of the heavenly treasures, said to contain the purest form of lightning. The Tower is part of seven heavenly treasures used during tribulations and has nine levels.
Fruity experienced the first level when he was becoming a Sage. Klaus was currently just a Master stage expert entering the Grandmaster stage. He was still two stages away from becoming a Sage, yet the Tower appeared.
One might expect Klaus to panic; instead, he was happy to see the Tower.
"If Yuying was right—which I know she is—then this level would contain very pure lightning energy, something akin to a Tier 8 core belonging to a lightning-based monster." He smiled.