If Lyod hadn't held back her power, if Letti had used her true strength, at least she wouldn't have suffered a crushing defeat like this morning. Or maybe, she could even win, judging by Aria not using magic and only using it when no one could see them.
That meant Aria wanted to hide her true strength or perhaps keep it to give her opponent a surprise attack.
Either way, Letti's chances of winning against Aria were higher than when Lyod forbade her to transform.
However… every decision must have a reason, and every action must have a consequence. Letti had freed a group of elves who had bad intentions toward Aria. It was only natural that Lyod had punished her by threatening her.
Supposedly, the culprit who released the prisoner from the restrained prison was sentenced to death. Or he would be dishonorably expelled from the pack. Yet Lyod was willing to forget about it and withhold her power.