This looks like some kind of hidden compartment that can be activated by pressing it.
Ji Chen didn't let his guard down in the slightest. He left a Murloc Ranger behind and led the rest of his troops back to the stone door, preparing for any unexpected situations.
After the Murloc Ranger pressed the brick, accompanied by a scraping sound, a section of the wall on the side slowly opened to both sides, revealing an entrance.
Ji Chen didn't immediately approach. Instead, he let the Murloc Ranger go in to investigate.
A few minutes later, the Murloc Ranger emerged, unharmed, and signaled that there was no danger.
Seeing this, Ji Chen walked over with a relieved expression.
In this Lich's laboratory, being cautious was of utmost importance to him.