Marigold, the remaining members of the Crepuscule Clan, and the other survivors observed the devastation of the Crepuscule Auction House from their respective ships. Even now, they were filled with disbelief. Less than a day ago, they were on that plane, with some taking part in the open auction. Now, it lay in ruins, and most of them were unaware of what had transpired.
The Crepuscule Auction House was no ordinary plane, with it being half artificial and half natural plane. Though most were unaware of the details, knowing the Crepuscule Clan's specialty and wide range of treasure, they would definitely have made sure their plane would stay intact even if powerful mages came picking up a fight. Most clans were also convinced they had enough defensive counters against The Emperor.
For this reason, the scene before them was indeed a sight they never expected to witness.
Furthermore, the one who came and destroyed it was The Emperor and an unknown 'mage.'