It basically has to do with the agreement when Crowther sold the design rights to Rogue that Crowther was still allowed to build Nebula, just couldn't sell it as Nebula. Crowther was contacted to build for Arsenal, but that was way over Hans head, so he had Dynamic start doing the builds for them but then they backed out and that was around the time USSC started building for Arsenal pretty much full-time. I know that Tom Eilerman redesigned and created most of the new Arsenal machines, so now, it's basically Arsenal's line since designs have been changed.
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