From MC's perspective:
Time went by,
2 hours later,
I found no activities outside. The movements stopped more than 2 hours ago. But still I had to wait to confirm my safety.
Swoosh~
I appeared outside. The concentration of the weird gas was lower and it won't affect me anymore.
Then I looked around and apart from the footprints there was nothing on the ground. After taking a glance at the footprints. I started walking forward.
Time passes in a blink of an eye,
Several minutes later, I came across a big opening. The opening gap was the size of a 10ft door. But the door was missing.
When I walked forward to inspect. I saw the traces of footprints again. Someone must have entered further.
I raised my head to look ahead. But complete darkness came into view. After calming down my heart, I started walking further.
20 minutes later,