Seems like they're preparing a new part of Time Temple.

Also, where would the dark witch fit into this equation? The one you fight in the final Cygnus quest. She's clearly stronger than Orca, weaker than Von Leon, and has a purple cloak instead of the typical blue one worn by the musclemen.

+1 for remembering about the Dark Witch. She alone was able to set a trap, petrify all knights and Cygnus and take over Ereve. As far as I remember she flees when you beat her, but if Orca can be a General (she probably wass holding back on Mercedes) I'm pretty sure Dark Witch is one aswell.

Maybe her true form...is a giant

I wouldn't be surprised if she could transform, just like Von Leon. In fact, what if all generals got to transform to let their true power out? That would explain why they seem weak in human form. Akhyrum could transform into a Giant Snake/Basilisc and his true name could be Tom Riddle