Artie actually discovered… that she could equip the demon soul ring!
Even if the ATK was stuck at 250 like the base of Banishment, it was better than nothing. The demon soul ring would continue to circle around her and attack enemies that would come near her. It's a no-hands weapon. This discovery was brought over by the existence of the hellbound rings Estrellas… and the fact that she found the demon soul rings in her weapon inventory instead.
It would be a pain to actually swing around while killing off the rest of the two hundred beasts. Since the ring would be hitting the enemies at the same strength as Black Havina, it would be helpful for her to do it. Then again, as for the consequences of wearing it on her body, only the survivors would know what she had.