Ding! Ding!
Her experience points kept rising and rising as the monsters around her died. Reina's buff was completely on the offensive side. She didn't place any defensive spells over her people. The spells' manifestation was that of a purplish shadow mist that covered their bodies and their weapons.
Aria borrowed the blessings of her spirits as well and enchanted herself, essentially creating a maniacal killing machine out of herself.
Her sword was swung carelessly, yet in an effective and swift manner. Whatever the Xagas shifted into, they were beheaded by Aria in an instant and hit by an elemental spell that finished them off.
Aria was so confident partly because she knew that she was going to advance into the next level sooner or later. Thus, she could just slaughter all of them until she was dead tired, and recover herself using the System's convenient regenerative ability.