[Tbolt]

Originally Posted by jopjopjop

Truth Idea chose Issei's dream at that particular battle, not the spear itself.

Spoiler:

Cao Cao must have used the spear to break the barrier to help DxD since he will most likely be an unofficial member of it.
And IIRC it isn't Rizevim's barrier. It's either Ladon's or Azi Dahaka's.

N0m@n responded to what the spear did with a spoiler.

Spoiler for spear:

The spear showed up by itself, Cao Cao didn't bring the spear.