THAT PERSON (2)

It means, "that person" is confident that he could duke it out by his lonesome against the Six Great Powers.

And that is a terrifying thought

The Six Great Powers also did not forget that Death Monarch is not a lonesome figure anymore. Even before, when he was alone, he was already a formidable figure.

Bur now, he is no longer a lone wolf in the world.

He has Pandemonium. Inside that land, there is many great heroes and heroines of the world.

There is that loyal Wang Jian, the cunning trickster, the genius Alchemist just to name a few. Those three people alone could wreck a lot of chaos all over the world.

Pandemonium did not lack powerful figures that could shake the world. 

Take any random person on the top echelon of Pandemonium and let him or her out and they could create more than just a ripple in the world politics and affect the actions of Great Powers of the world.

Everyone knew why Death Monarch drafted the Article.