Zzzap destroying walls effortlessly / slicing off a man’s arm

The wall crumbled to ash as the blazing wraith passed through it. The shadows fled the room. “Bite,” said St. George. “Left arm.”
Zzzap nodded. Understood. Do you have him?
Lynne’s eyes were wide and wet. “What are you doing?”
St. George grabbed Mark by the shoulders and pushed him flat on the floor. Lady Bee grabbed his wrist and stretched the arm out straight.
“What are you doing?!” Lynne tried to pull St. George away. He shoved her back against the wall with one hand.
Sorry, man, buzzed Zzzap. This is going to hurt like hell.
Mark gritted his teeth, squeezed his eyes shut, and nodded.
The gleaming outline dropped its hand. The fingers swung down and passed through the man’s biceps. There was a hiss, a puff of smoke, and Lady Bee fell back clutching the arm. Mark screamed while a scent like burnt barbeque filled the room.

Excerpt From Ex-Heroes, pg 108-109
Peter Clines
https://books.apple.com/us/book/ex-heroes/id585738407