Dr N.Gin, Cortex's right hand man... or was, while he was working for him, to say the least. N.Gin's always been a friend of Neo's ever since their days back at the Academy of Evil.
N.Gin is a specialist in rocket science and cybernetic biology. A physicist, to be precise. He always loved working with these since his childhood. And when he got older, he became very famous for making people cybernetic limbs that were very realistic and useful.
Though unfortunately one day, while he was in his rocket lab, working on projects with Neo Cortex. But as Neo was fiddling and being nosy with the various rocket experiments around... one of the rockets go out of control by mistake and strike N.Gin in the head! Neo is actually horrified with what had happened, and he helps N.Gin at the scene. He didn't mean to do it of course, but he decides to try and save his friends life, at least. Unfortunately, Cortex had to keep the rocket in N.Gin's head, because if he removed it, he'd just die. N.Gin soon recovers and thanks Cortex for saving him and swore that he'll do anything to help Neo ever since. N.Gin never knew it was Neo that caused the accident though... as Cortex was too cowardly to tell, and Neo didn't think he'd need to, since he didn't do it on purpose.
Sadly though for N.Gin, after that accident... he became feared by most people, and wasn't even allowed to help patients with missing limbs anymore, because of his appearance! Also, the rocket in his head sometimes made him act a bit strange... N.Gin decides that they're not worth it, and he just carries on with his other hobby, rocket weaponry making... and helping Dr Cortex with his evil schemes.
More Detailed Information:
During this time, N.Gin was looking after Dr Neo Cortex's Space Station, up in space. And in 1997, during the time Cortex was plotting to destroy Crash... he helps with capturing many of the anthros back on Earth to bring up into space.
He doesn't quite get along with any of the minions, because most of them think he's ugly and/or funny, and often poke fun at him... making N.Gin rather moody while dealing with them.
Around about 1 and a half years later... he encounters something rather horrific. While searching around the labs for mechanical equipment, he comes across Nefarious Tropy, who just walked out of one of the labs, injured slightly. N.Gin asks him where he can find some screw drivers, but Tropy warns N.Gin not to search in there, because of an accident involving Cortex. N.Gin gets alarmed and then quickly goes in to the lab to help Cortex...
But then he finds someone else in there, he saw Crunch laying on the floor badly injured, though he did see Neo but he was only knocked out. N.Gin, at the time didn't know what had happened but he immediately got help for Crunch, as he took pity on him at that time. N.Gin is shocked at the large amount of blood all over Crunch but then he notices that it's coming from his arm. Crunch was still conscious, so he used an anaesthetic on him to make him calm and go to sleep for a while.
Later, N.Gin then realizes there's something really wrong with Crunch, and then tries to ask Cortex about it. Dr Cortex is angry to see Crunch again after the 'accident' and tells N.Gin to put him to sleep! N.Gin refuses of course, but Cortex tells N.Gin that the laser that was used on Crunch will eventually kill him anyway. N.Gin is bothered with what Cortex did, and finds it unacceptable and unfair, as other minions do worse and yet they don't get punishments near as bad. Cortex soon leaves anyhow, believing Crunch ends up dieing... but N.Gin figures out a way to save him, but he had to remove his whole forearm and replace it with a robotic one. This was difficult for N.Gin to make, as he's never worked with animals before, only humans.
But a few days later, he manages to complete it successfully, and Crunch starts to wake. he explains what's happened, and Crunch is very grateful for N.Gin's actions, and treats him with respect from then on. N.Gin decides to let Crunch live in his area of the Space Station, so Cortex never knows he's there...
Over the next few years as Crunch grew into an adult, Crunch asked N.Gin if he could help him train up to get stronger. N.Gin thinks it's a good idea, as N.Gin could also test his Mech's against Crunch, to see how good they are. Though as Crunch was growing, his metal arm gave him problems.. because he was growing too big, too fast. N.Gin had to keep modifying it because of that.
When Crunch was finally an adult, it was around the time Dr Cortex decided to try destroying Crash again and taking over the world! N.Gin found it to be a bit of a bore, and didn't seem to take much notice. Though now that Crunch was fully grown and dangerous, N.Gin started to worry about Neo Cortex's safety... especially after Crunch mentioned his plan of sneaking into the upper part of the Space Station to slay Cortex once and for all. N.Gin did respect Crunch, but he also respected Neo, probably more because Neo has been his friend most of his life, despite the bad things he does... he was struggling to decide if he should tell Cortex that Crunch is still alive, or just leave things as they are...
That's until Neo one day was walking around N.Gin's areas of the Station and caught N.Gin muttering to himself after chatting with Crunch. Neo knows N.Gin is up to something and then N.Gin finally tells Cortex everything. Neo is scared at first and wants to try and get rid of Crunch! But N.Gin tells him no, and that he's an excellent warrior. Cortex then thinks, maybe Crunch could be useful for killing Crash? So N.Gin shows Cortex how Crunch is, and this is when N.Gin betrayed Crunch.
Crunch was very angry, of course and he also scared N.Gin! But he wouldn't harm him... and soon Cortex and his gang of Lab Assistants capture crunch with sleep darts, but Cortex almost got attacked in doing so! From this point on, N.Gin never sees Crunch again... only while he was under control, and he was a much different character then.
N.Gin is (c) to Activision