In thinking back on the various characters and adventures in my campaign, I can think of a lot of interesting relationships that brewed up organically from them. Some of the most interesting of these were the various characters and their personal nemeses.
Once I really started getting into Star Wars, I began to realize the value of trying to keep villains around for an adventure or two—to build them up, just like the characters. In retrospect, it should have been a no-brainer, but when you come from a D&D tradition, the 'enemy' is usually killed at the end of the adventure and you go on to the next one.
Since I don't feel like forming a coherent argument or rational discussion at the moment, I'm just going to list the various characters and what I remember of their nemeses.
1) Arianne Volar: Her first real nemesis was Bane Nothos—whom she first encountered obliquely in the adventure 'Strike Force: Shantipole'. She ran into him again in Otherspace, and then once more in Otherspace II (even though she had accidently 'killed' him in Otherspace). The two of them were 'ship captains' so the animosity kind of had a nice symmetry. But it wasn't until Bane's niece, Rina Nothos, showed up that Arianne really found her mirror-mirror image. Rina even went as far as to gather a group of rogues around herself, specifically designed to be a match for Arianne and the whole Vermillion crew. The two showdowns that these groups had were both very memorable. To my delight, the first encounter was a complete victory for the villains. Dramatically, the second encounter found Rina and her crew taken down QUICK by the this-time-prepared vermillion team. Rina somehow escaped, though, only to be 'lost' later into a time vortex (the same one that got the mandalorian, Oman). She of course returned and sought vengeance on Arianne—this time managing to kill her father. Arianne managed to track down and capture Rina again, but...well, she's not dead, so who knows what the future stores.
2) Adren Olin: Wow, could she make enemies. Though, truth be told, her main line of work was to 'convert' bad guys to good—something she managed to accomplish with a would-be warlord: "Faarl the Conqueror" and a disillusioned Imperial Admiral (Kermen). As far as a true nemesis goes, however, Adren had two. The first of these was the increasingly obsessed and insane ISB Agent Barezz—a man dedicated to eradicating the 'impurity' of Force powers from the human race. He experimented with all manner of anti-force technologies and genetics (a hybrid human-ysalamiri critter). He was also an avid cloner. This took the form of actually cloning Adren (with the intent of using her against herself) and making copies of himself. "Barezz" has "died" several times now—but he keeps coming back. Kind of like Agent Smith (if you'll forgive the Matrix reference). As formidible as he was, though, Barezz wasn't Adren's only nemesis. Lord Qar, the foppish, narcissistic, swishy and thoroughly corrupt sith Lord is the one who REALLY pissed Adren off the most. And he was an especially frustrating villain because nothing seemed to phase him. Very much like the Joker from Batman, he was a maniac and sociopath who had nothing to lose and inflicted woe upon Adren simply for his own pleasure. He too was apparently 'killed', but the circumstances of that death were strange indeed (another time-travel adventure) so.. who knows.
3) Rick Oman (aka Mandalore). Strangely enough, the 'nemesis' through most of his early career turned out to be his future wife—Zardra, the femme fatale from Tatooine Manhunt and Otherspace. It began as an uneasy and short-lived partnership between Zardra and the Vermillion crew to escape Otherspace. She showed up from time to time as a bounty-hunter, usually working against the group. And then she totally sent the group into an ambush, one that took them to a darkside nexus (Domain of Evil). When she encountered Oman afterwards, she actually felt guilty about it (and was secretly impressed that he'd managed to survive). Thus /really/ began their relationship, and it remains an interesting one. Only much later in his career did Oman develop another real nemesis, and sadly this was rather short lived. Boba Fett (who Oman had actually worked uneasily with before) tried to assume the title of Mandalore, determined to lead the clans into a hopeless but bloody blaze of glory. Oman opposed him. The battle was of appropriately titanic proportions. Fett died.
4) Horatio Flynn. As a late addition to the team, I've never really had the chance to develop a nemesis for Horatio, but I think he's managed to develop one for himself: Arianne Volar. It all began with a playful scheme to hit on Arianne's adopted ward, Reen. But then it turned into a relationship with said ward. Exactly how serious it is remains to be seen, but Arianne is playing the role of protective mother-figure to the hilt.
5) Bob the Tusken Shaman. Shame on me, but in all our adventures, I never really developed a personal nemesis for Bob. Oh sure, he squared off against Lord Stromm (see below) a time or two, and several other Dark Jedi types, but I'm not certain any of them could really be called 'his' enemy alone. It could be that Bob was one of the most laid-back of the Characters—in essence, he really was a good Jedi. He didn't hold grudges. But...well, like I said. Shame on me. I'll have to work on crafting him a rival. I guess the closest thing Bob had was his uncle Frank (a recurring joke in the campaign)—Yes, uncle Frank had 'anger issues' and would often go out and club young moisture-farmers then try to ransack their landspeeders. Bob has had several talks with Frank, trying to help him work through his issues.
6) Harry Hugganut. Harry was just too laid back to have any real nemeses. What he had were more...rivalries. The first of these that I remember was during the 'Captain Fandar' adventure. While trying to impress and recruit a pirate to the cause of the Rebellion, Harry could not resist making fun of the pirate's unblinking, devaronian gunman sidekick—nicknaming him "Blinky". And then there was Crisis in Cloud City, where Harry's player CHEATED IN REAL LIFE at a card game to beat out a disguised Lando Calrissian in-character. Thankfully, Lando had a chance to redeem himself. When a rogue droid crashed into the casino, and everyone went scrambling for cover, Harry (completely in character) tried to make a grab for all the loose credits. Much to his chagrin, Lando had beaten him to it! About the closest thing to a 'serious' nemesis Harry had was Rina Nothos' hired gotal gunman, but that never really had the time to develop.
And finally, there is one special case that should be mentioned: Lord Stromm. I created him to be the Sith Lord nemesis for the group—a 'mini-Vader' if you will. The first encounter went well enough—a battle between Stromm, Arianne and Bob that was indecisive, but managed to introduce the villain. But soon after came the dreaded 'M13' incident (which the Empire and Sith order both categorically deny ever happened).
I had manipulated the characters into trying to rescue an informant from a remote and 'lightly guarded' Imperial outpost (M13). Things were going well for the Empire. The characters reached their informant to find him dead—and were then suddenly attacked by Stromm's entire task force. An AT-AT, Two AT-ST's, a company of special Stromm-Troopers (dressed in black stormtrooper armor). A squadron of TIE interceptors and a Strike Cruiser. Yeah, I was really going to show the players who was boss!
And then, everything fell apart.
The details are hazy to me now, but the entire situation turned into a route for Stromm and his men. The high (low) point in this debacle was when Bob used his telekinesis to make a ramp for a landspeeder driven by another in the group (Harry, I think). The two of them rammed the AT-AT in the face, taking it down.
Unfortunately, this seemed to set the tone for the rest of Stromm's appearances. Every time, a combination of bad rolls and mistakes by me resulted in the Sith Lord fleeing for his life. In fact, his injury-prone lifestyle even prompted him to include auto-medpac-injectors in his armor. Sad.
In the end, he went out like a punk. The party was on a Super Star Destroyer and were, for some reason, split up. A perfect time for Stromm to strike! He found Bob alone with the NPC Reen. Stromm and Bob dueled—a duel which turned inexorably into a 'jedi fist fight' (as we came to call them). And then Reen stepped in, with her pitiful 4D blaster skill. She took a pot shot at Stromm as he batted Bob's limp form away. And my dice completely failed me. Stromm was taken down. Oh, his med-injectors assured he got back on his feet, but only just in time to get shot in the head by Oman (who had correctly guessed from afar that it was Bob who was the 'prone one'). Thus, with smoking blaster holes in his death's-head motif (TM) helmet, Stromm plummeted down the turbolift shaft to his death.
He died as he lived—pathetically.
So, he wasn't much of a nemesis, but he was memorable. That's something, right? In any case, a good (or even a bad) nemesis can spice up any campaign!