The powerful being that was blocking their way did not have a body like most living beings. It was in a state of colourful gas that was constantly changing its colours. But when this being initiate an attack, it could make its body solid and very hard.
As for this being's powers, from what Rein had observed, it was unable to use any kinds of long distance attack. But it was very compatible with the space of the void, so this being was capable of moving very fast, almost instantly in this void. So the lack of long distance attack was not even a problem for it.
As for how this entity attacks, it did nothing special and just attacked in a straightforward way.
But that simple straightforward attack was able to split the solid and compact space of the void like a knife through butter. Its attacks were extremely fast and dodging them was almost impossible. So Rein would be trying to keep this monster as far away from him and his lovers as possible.