Not truly a trait or skill, it is a god-like ability to read the enemy and know their next move during battle. Most high level adventurers could do this to an extent but Kang Hansoo was unique even out of these people. This ability was named by Kangtae as Battle Foresight.
It was developed by Hansoo from an immeasurable amount of battle experience and knowledge from 50 years of fighting in the Abyss. Since Hansoo could only learn seven skills, the only way for this trait to shine was to become strong in a different way than others. And because of that, unlike the strong people who climbed relatively easily, he had to go through many more times worth of battles and struggles in order to climb up slowly. But this had made him stronger after. Since being able to read the enemy and knowing their next move was an overwhelming advantage.
In chapter 223, we find out the following:
At the same time Hansoo’s brain started to work quickly.
An ability born from his battle experience.
Once he used it then everything around him would look as if it had stopped.
‘Phew, So I need to use at least this amount of mana to use this huh.’
Hansoo mumbled as he felt the Mana Jade that was rotating intensely.
Of course it wasn’t like he could move quickly in this stopped world but the fact that he could think and judge clearly at normal speed was a tremendous bonus.This means that his Battle Trait also has a secondary ability to make him think at high speed but it uses a lot of mana to do so. He is only able to start using this aspect in the Green Zone when he has the Mana Jade.