The four cast a shield, one barrier per person, forming four layer barriers as Tang Shaoyang slashed his sword. They reacted in time despite how quick Tang Shaoyang was. But the barrier was rendered useless by Tang Shaoyang's slash.
He applied [Absolute Domination Energy], easily tearing apart the four-layer protections. The sword went through the four bodies at the same time, slicing them apart. It did not stop there as Tang Shaoyang also formed four blades made of Chaos Energy.
The black made of pure energy formed above their heads, each person had a blade pointed at the back of their heads. As their bodies fell off, the blade struck their head.
Tang Shaoyang did so because he only heard two kill notifications, meaning there were two still alive after getting their bodies sliced apart. With the Slayer Blade, he killed the remaining two.