Those nail marks are the traces left by anti-slip ground spikes.
When Zong Shen strolled to the entrance of the Lord's Small Tower.
He saw the condition of the door firsthand.
That's when he realized why he couldn't push it open.
The entire door was encased in ice. Although the ice layer wasn't as exaggerated as on the ground,
it was still very solid, forming a sealed ice shell.
There were some not-so-obvious cracks at the corresponding position of the door.
These were the results of Zong Shen's previous attempts to push the door open with force.
Now he was ready to break the ice from the outside.
This way, the door of the small tower would not be damaged.
After a brief contemplation.
He flipped his hand and took out a weapon.
Heavily drove it into the ground!
The ice layer outside the porch left a cobweb-like mark from the strike.
This was a trident about two meters long.
Its design was somewhat similar to a long-handled fish spear.
