What is the deal with Gyges? Episode 4 strongly hints there are deep secrets to Gyges but doesn't fully explain these mysteries (probably on purpose, given that the entire first half of Episode 4 is explicated in detail).
My best guess is that Gyges is a living planet and as such many of its alien organisms have various degrees of interconnections with the "minds" of the planet. There may not be a central leader of this "hive mind" per se, but rather powerful personalities amongst the collective may have great influence over what the planet does and the sort of creatures it spawns.
General Zinglon, as a result of his "accident" during the matter transporter demonstration during the Not-so-Great Gryphon explosion, may have accidentally merged his DNA and organs with the planet Gyges (which may or may not have been the intended destination of whatever was meant to go through the matter transporter.) Of course, this wouldn't necessarily rule out his image appearing on people's vidscreens as the transportation was happening or even afterwards as a result of either how the device worked or the powers of the planet, or both. Anyway, this would explain why Gyges seems to have a connection with Zinglon (and can grow creepy versions of human organs and tissues as enemies) in Episode 4, although Zinglon is not the only major personality in the hive-mind (there is also the Great Stomach, for example, and their aims appear to be at odds as the Great Stomach has no love for Microsol and attacks Trent for unwittingly working for Microsol in Episode 2). Still, Zinglon (or at least this new Gyges-Zinglon personality), may wield a lot of power nonetheless (at the possible cost of Zinglon's sanity).
It may have taken a while for Zinglon's consciousness (or this version of it) to start manifesting on Gyges due to the nature of how Zinglon came to be merged with the planet. In any case, Microsol may be aware of what happened to Zinglon and merged Vykromod with the Nose of Zinglon on Gyges to test/prove their theories and strengthen his consciousness. They seem to succeed at first, with Vykromod becoming a creepy mutant nose-face organism of mass destruction, but obviously Trent puts Vykromod out of his misery and the organization continues its fall after that. Nonetheless, an obvious problem remains which is that Zinglon may be dormant again but he is likely still part of Gyges and thus a potential future threat (amongst others).