Because they were currently within the Eclipsing Shadow Domain, Damien wasn't able to see the grandeur of Twilight Moon. He could only feel the terrifying energy approaching his back as his sword swung downward.
But for those outside the domain, their entire worlds had just flipped upside down. The sun in the sky was covered in a black veil in an instant. Dark clouds blotted out the skies and shadow crows flew wantonly through the air.
The ground within many kilometers was directly corroded and melted, creating a pit that enveloped the surrounding practitioners and even directly killed a few.
As for those who died, they could only blame themselves for treading too close to a battle between people with 4th class power levels.