Grey didn't want to let go of such a weapon, even in the Gnome world, except for those Half God experts, he was sure this miasma will be able to threaten even those close to the Peak of the Sovereign Plane. The miasma he had in his body has gotten stronger, but it isn't enough to kill those Late stage Sovereigns within a short period of time, whereas for this miasma, it would almost instantly take effect if pumped into the body of a Late stage Sovereign.
This was a powerful killing tool, he didn't want to let it go. Of course, if he didn't have any other choices he would give up on the opportunity, but for now, he wanted to try to see if there's a way he could store this powerful weapon for some time. He was racking his brain on how to store it when some slipped out of his body. Due to his breakthrough, his aura fluctuated and he lost control of the miasma, allowing a tiny bit to slip away from his body.