Rex meticulously controlled his kingly energy—mastering both the Blood Moon and Banished Dark Moon powers. His command over these two energies, was forged constantly, becoming a little bit stronger with each battle he has gone through.
Now, his energy control had reached new heights after his encounter with the Fifthborn.
He could condense both types of kingly energy, despite their different nature.
In deep concentration regardless of the chaos around him—the two kingly energies gathered into the palm of his hand, with minimal friction. Feeling the immense power the Demon Origin possessed, though he was only a fragment, Rex decided to heed the System's advice.
During his first try to turn Caraptaros, the System had given him the necessary requirements.
Rex knew he needed three King Marks to overpower the Demon Origin's fragment within.