Ever since Gul'dan's Skull had been stolen from Dalaran, the war between the Scourge and Dalaran had ceased for an entire day.
During that day, the Scourge did not launch its customary attacks, and Dalaran no longer took the initiative to provoke them.
Both sides tacitly withdrew their reach and remained within their own territory, focusing on their respective tasks.
As for Dalaran, they had more or less guessed what their opponents were doing and were actively taking countermeasures themselves. They were fairly confident and had not encountered any major problems.
Their only concern was that the enemy might summon the demons before the floating city was completed.
As for the Scourge, Kel'Thuzad, once a legendary mage, had realized after obtaining the magic for constructing a portal from Gul'dan's Skull just how enormous a ritual would be required to accomplish it all—and that the ritual's magical fluctuations would inevitably draw the attention of Dalaran's mages.
In fact, under his orders, the entire Scourge had long been on high alert, prepared to deal with any mages who came to stop the ritual.
Yet, to his and Arthas's surprise, Dalaran showed no reaction whatsoever.
Kel'Thuzad racked his brains but could not figure out why.
Having once served among Dalaran's upper ranks, he knew perfectly well that Dalaran possessed a system for monitoring abnormal energy and spatial fluctuations.
Disasters caused by forbidden magical research or taboo summoning rituals were not unprecedented in Dalaran's history.
That system had been established precisely to deal with such situations.
And the Scourge's demon-summoning ritual was exceedingly conspicuous, both in the energy it consumed and the abnormal spatial fluctuations it produced.
It was practically the same as setting up a loudspeaker outside a police station and announcing, "I'm going to do something bad! I'm going to summon demons!