The audience couldn't believe Eren would use Grim Pillar Town as a threatening tool.
At this point, the pillars in Grim Pillar town kept on growing as more and more pillars would get erected overnight by some unknown entity. All these pillars were dedicated to rankers who were perceived to be Eren's enemies directly or indirectly.
Nobody wanted to meet such an end where their remains would serve as an art collection for someone else. Nobody wanted to be an inspiration for their future generation by claiming a pillar in the Grim Pillar town for themselves.
Even Expert-ranked entities in the audience didn't dare make any noise because they knew someone like them had once messed with a certain wrong guy. They didn't want to follow in his footsteps.
Eren flashed a graceful smile as he observed the pin-drop silence. He took a fresh nightly breeze into his lungs before speaking up.