He is using Aimbot hack.

It is obvious that he is using aimbot if he sees the whole video

Please pay attention to the part I give

・3:12~

He has an aim on the stairs

An enemy appears in the back snow and Aim moves at high speed

Because he does not notice the enemy, Aim will return to the stairs again at high speed

・4:42~

He aims at the enemy in front of him

I will also aim the enemies who ran from the base

And Aim back to his front enemies

Auto aim specific behavior

・5:07~

・5:24~