Ah, cathodyne. That's right. But the LTP is just way better. It has better supply noise rejection. It overdrives really nice. And it naturally supports feedback from the OT which is kinda important for a clean amp.
This Dark Terror thing is obviously for bedroom metal sounds with five (5) cold preamp gain sections and that "shape" control and a wimpy output. But again, I think that's a goof. My impression has always been that large grid stoppers on a negative bias output created the swirling roar of a metal amp because the tubes rectify the grid current limiting and charge up the coupling caps making it into an envelope filter of sorts. But I'm not playing Black Sabbath anymore so whatever.