The Trump Card.

It is as the Celestials feared. Aeternus is not foolish. He will not be in a sorry state despite how everything looks. In fact, he is no danger at all. He can pass through the onslaught of attacks unscathed without doing anything if he wants to. 

But he has to act as if he is in danger. He will do what they expect him to do in this sort of situation. He will reveal what is supposed to be up his sleeve. Because without this trump card, he should be in a sorry state. It is only normal for him to reveal it now to get out of danger.

The black round spot on his face suddenly bulged. It is like something is inside his head and is struggling to come out. The bulge expanded outward then it collapsed inwards suddenly. Everyone expected an explosion from his face so they were surprised when the bulge collapsed to become a whirlpool instead. The strange development of Aeternus's face didn't end there.