Alex would indeed test it.
He looked toward the five in front of him, and quickly looked away. There was no way he would be testing something this dangerous on their person. Maybe it would be fine if he did it with Whisker, considering his Undying Physique, but he didn't trust Whisker was strong enough to come back from something that could be as devastating as this.
So, he tested with a storage bag instead.
He found a storage bag inside of his Soul Space and placed some random items into it. Then, he pulled it out.
As soon as the storage bag appeared out of his Soul Space, Alex and Pearl sensed something happening to the storage bag right away.
The bag seemed to stretch behind him, as though being dragged by something, until it could not hold itself. The space within the bag burst apart first, turning the bag to tatters, and even destroyed everything that was inside. The broken items lay on the floor of the ship in an unrecognizable mess.
