The Ancient Dragon Empress had clearly paid a price for her choice to kill Ao Xianyu as quickly as possible.
At the very least, she had sustained some injuries.
Her battle style was very aggressive and radical, and she was most likely doing this to try and eliminate all of her enemies as soon as possible.
If the passageway between the two worlds could be opened up in a short amount of time, then they would most likely all fight more defensively in order to stall their opponents.
However, the evil dragons had chosen to take the initiative, and all of them were trying to slay their enemies at all costs.
They were doing this to strike fear into the hearts of their enemies, as well as to deny them the opportunity of gathering together and combining their forces… This indicated that it would take some time to open up the passageway between the two worlds!