Richard and the other soldier had to suppress a gasp in front of that bright purple-red light. They felt utmost respect for Khan, especially after his landing, but that color remained a synonym for danger. Even experienced warriors would hesitate before the chaos element.
Khan noticed that but didn't care. Generating those reactions was actually for the best. Acquiring a superhuman state was the first step toward the status he required. That would raise a wall between him and ordinary soldiers, but he was willing to pay that price.
The wall at the end of that short passage looked sturdier than the other surfaces. Khan couldn't exactly see through rocks. He only felt a vague vibe that gave him that impression. Also, he could see the mark left by the previous drill, so he knew where his spell had to go.