After several attempts, I've finally won a One City Challenge on Noble - got a diplomatic win in 1959. Whilst I was well chuffed to have won, it did leave me feeling slightly guilty for using dirty tactics to get there. Nothing silly like reloading and going back, but just using tactics that would leave me fuming if the AI ever tried it against me. I started on a continents map, everything else random. I got Frederick on a small map. I couldn't find the coast quickly, so I settled in a nice spot next to a river, but inland. That ruled out any possiblity of a conquest win. Obviously domination, cultural and time were out of the question as well, so that just left diplo or space to shoot for. It eventually turned out that I was on the larger of 2 Islands with Monty, Hetty and Peter. The other Island had Julius & Lizzy. Monty got taken out early on, leaving just the 5 of us. I was to the South of my Island, surrounded by Hetty, who I kept either Pleased or Friendly. Peter was to the North. I was able to keep up with Tech, building a small lead by 1900, but having to keep trading new techs to keep everytbody sweet. I could see there was no way I was going to win a Space Race with only one city and no head start, so I beelined to getting the UN built. I had an adequate military to defend with by this point (about 30 marines & infantry, with a few cannons), but no oil for tanks. Not enough for an all-out offensive against anybody. Once the UN was built, it turned out that Lizzy & Hetty were pleased/friendly towards me and each other, but were sworn enemies of Peter & Julius, neither of whom were ever better than cautious towards me. Unfortunately, the other side were both slightly larger then Lizzy, Hetty & I put together, so I didn't make it to Secretary-General - Peter got it. It soon became apparent that I was wasting my time buttering up Julius and Peter, but didn't have enough votes without either of them. The first thing Peter did was get the anti nuclear proliferation passed, so Nukes were out. Then I realised - I had plenty of votes - it was just that they had too many! I had just over 10000 gp available, so I pumped out 5 spies (which I've never found useful before), and used them to sabotage every single improved square of Peter's land (200gp per square). I had to cut my research back from 100% to 60% to get extra gold, but I got every farm, mine and cottage. It took a while to bite - then all his size 14+ cities plummetted to size 2, all his military disappeared - I sent in 10 marines and wiped him out. Hetty & Lizzy picked up the empty space (I sabotaged any improvements that Julius tried) - and next vote I had enough votes, and victory was mine. Satisfying - but I can't see how you could defend against such use of spies if the AI did it!