A battle between Martial Seniors.
It was not something that human beings were qualified to bear witness to under normal circumstances.
The sheer power output of Martial Seniors was so high, that death was a certainty even if the spectators were hundreds of meters away. Such was the destructive power of those who had harnessed the full potential of the Martial Body.
Of course, the Kandrian Empire most certainly possessed the powerful infrastructure needed to allow spectators to survive and witness the riveting battle between Martial Seniors. That usually came at the cost of freedom in battle.
In this case, the Martial Senior battle was not a commercial event.
Thus, neither side saw fit to bother getting spectators.
This was purely a duel for the throne.
For the future of Kandria.