Board Thread:General Discussion/@comment-26241376-20150324221237/@comment-15675979-20150326131344

good theory but I think it's unlikely

My theory is that the Blue Diamond is defeated and corrupted. But it wasn't bubbled until the events of "Horror Club " because I believe that the gem in the lighthouse is the blue diamond. For me, the crystal gems fused together and form a huge powerful gem that looks like the crystal temple. They defeated Blue Diamond and fall in the lighthouse. It become corrupted but defeated by Steven, Sadie, Ronaldo and Lars in "Horror Club".

And the Crystal Gems might be very proud at Steven as he say so after bubbling the gem.