'Fusion State'
This was the name of the technique that appeared in Grey's mind.
Just like when he got the technique for elemental fusion, this technique also appeared in his mind. He was sure this had something to do with the pearl he absorbed and the Chaos Element.
When he got the technique for elemental fusion, he just broke through to the Arcane Plane. From the details of the technique, it seemed like he was supposed to acquire it when he broke through to the Origin Plane.
But he unexpectedly acquired it sooner because of his current predicament.
The technique was similar to elemental fusion in some ways since it also involved fusing the elements. Only, this time, he had to fuse them inside him.
Unlike elemental fusion, the Fusion State required him to fuse each of his elemental beads into one.