Well clearly once we take care of the cloud of darkness, we will probably be heading into the bowels of the crystal tower, into the lands of eureka. There we are probably going to try and mess around with the crystal tower to destroy or seal is permanently. Possibly because cloud of darkness starts a chain reaction that can't be stopped by just defeating her and the void gate is going to be thrown open unless we can seal the tower up in it's foundations and poke around in it's guts.