Oh it was obscene amounts of stolen source code. Hodge podge of three completely different games (one of which was 2d!) that he combined together into some unholy hybrid. I genuinely have no idea how that thing even compiled, or if even he knew which files actually did what in the live game. Far as I know, though, he, or maybe an AI, implemented the STW inventory system. STW's code never got leaked to my knowledge, so everything that re-implemented STW was written for real at least once. The animals come from Humans Vs. Robots.
As for the idea of clones in general, I think I was one of the first people to really start using the term unauthorized code forks, due to the meaning of clone in the wider gaming world. A clone, or explicitly a concept clone, is not something I have a problem with. It is a game which happens to be very similar to another. Many first-person shooters were referred to as Doom clones in the early days of the genre. We are somewhat starved for genre variability in audiogames themselves, and many things got called clones just for operating like another existing game, even if that game was virtually alone in the genre. I think competition and iteration is good.
Unauthorized code forks, however, are games built off the backs of stolen source code. A great many of them were nothing more than rebranding or unholy combinations. Most of the TK clone lineage which eventually made its way into daily life and its successors actually was a hybrid of TK's leaked code and that of Humans Vs. Robots, made by possibility the actual developers of HVR themselves. I don't keep up enough with drama to know if HVR's code got leaked. I suppose if people want to fuck around with them in private I can't say much, but if you're out here in public, advertising it as your own work when someone like me contributed to the code you stole? I do not appreciate it, and I categorically refuse to host them or help them in any other way.