Shadowbane

It was a night raid. In addition, the enemy came in numbers: the strange looking magus, the pale peak rank 9 fighter and the dozen fighters dressed in black garb.

From Emery's side, other than his master Magus Xion, the next strongest person had to be Yuria, who should also be a peak stage rank 9 acolyte. However, it was evident she appeared to be troubled fighting against one of black grab warriors. She was fighting fiercely, her dancing-like knife moving against the opponent's large saber. 

Thrax and Chumo were also struggling against these mysterious fighters called 'Shadowbane'. Looking at the way they fought, Emery could somehow guess each of those warriors had to be a rank 9 fighter. This was the only possible explanation, as even the Terra knights, who were all rank 7 and 8 were unable to overpowered them with their advantage in numbers.