I still have a lot of flaws

Fein looked around the stadium, then at the unconscious monster on the ground. He raised his left hand in the air.

THUD! THUD! THUD!

A powerful rumbling deafened the entire stadium. The ground shook, debris rolled on the ground, and the people around fell to the ground as they couldn't balance themselves.

"What's happening!?"

"Is there an earthquake!?"

The civilians began to panic. They looked fearfully at the humongous trees in front of them. If one of the threes fell to them. They knew they have only one end.

"Don't panic!" Gregory yelled at the civilians. "As long as we are here, a mere earthquake won't harm you." 

The crowd turned their heads at Gregory and Michael who was just walking calmly as if the earthquake couldn't affect them. 

"This is not an earthquake. It's just the effect of our friend's ability." Michael added.