"Those ungrateful dogs bid their time and waited for the moment when I was about to complete the amplification device to enact their plan. Yozmogh attacked me while I was at my weakest, while Dann'Kah used his crystal to redirect the energy from my phylactery to their bodies instead of mine!
"You can imagine the rest." Zolgrish said. His skeletal body was now complete and he was standing on his own. The lich's blood core had returned to a normal size, but over half of it was black.
"So, after defeating you, they discovered they shared your limited freedom of movement." Lith said as Zolgrish nodded in approval.
"It explains why they didn't leave despite having opened so many exits, but not what they are fighting for nor why they attacked the nearby city alarming the residents."
