Klaus's sudden exit was just too shocking.
Right under the noses of 14 True Immortals, a level 7 Empyrean not only made a quick escape, but even an Immortal King had no idea how he pulled it off.
Just like the 14 criminals, Varkos was also in shock, watching as Klaus's body slowly turned to mist.
He tried to locate his other clones, but he was unsuccessful.
Naturally, if he looked outside of reality, he would have seen Klaus's clones. Something that doesn't exist in reality can also be found within the void.
Although the brat was all chatty and disrespectful, the truth of the matter was that right after the Blood Tournament, the real body had long since left the arena through the void and, using his understanding of the void law, had started creating a chain of clone bodies.
Klaus's escape was foolproof. He deceived everyone, including the True Immortal who had been keeping a close eye on him, with a mere illusion that had been made tangible.
