[Sia's Pov]
While Archer was stuck in Frosthold, thanks to the Death Mist, Sia was battling her way north through the Underrealm while leading the monster army Mary brought together, but she was now worried as over half of them were dead.
Three Warrior Spiders died, leaving over a hundred standing when the battle stopped. The Swarms commanders stopped sending their creatures to them as other stuff was happening.
As Sia traveled down the tunnel, a wave of horrifying shadow creatures washed over them, but nothing happened. That's when she sensed the mana. It was familiar to her, and after focusing on it for a few minutes, her eyes widened.
'Their Archers! They must be part of that shadow form he turns into,' she thought.
