Helpful Legion.

Some demon gods decided to take PRIDE up on its challenge. They also attacked the barrier to see what was so difficult about it. 

LUST's whip, made of soft and highly infectious energy, failed to harm or adhere to the barrier. GLUTTONY's corrosive energy failed to corrode the transparent barrier too. 

SLOTH didn't bother to try because it was sleeping. Besides, its energy is not good for attacking. The other demon gods didn't have its excuse, but they also decided not to bother so as not to embarrass themselves. 

The demon gods finally realized that the barrier wasn't as simple as it seemed. They were late to that conclusion by half a step. Aeternus already knew its nature before he tried, so their failure didn't surprise him.