Civ4 AI Survivor Season 6: Championship Game Alternate Histories


Introduction

Championship Game Alternate Histories Spreadsheet

One of the recurring features of past seasons of AI Survivor have been our "alternate histories", running additional iterations on the same maps to see if the same events would play out again. The Season Six Championship surprised everyone with a powerful Churchill and a Mansa Musa who somehow avoided being dogpiled en route to a Cultural victory. Was that something which would unfold in each game? This was a topic that called for more investigation with alternate history scenarios. Following the conclusion of previous seasons of AI Survivor, I had gone back and investigated some of the completed games and found that they tended to play out in the same patterns over and over again. While there was definitely some variation from game to game, and occasionally an unlikely outcome took place, for the most part the games were fairly predictable based on the personality of the AI leaders and the terrain of each particular map. Would we see the same patterns play out again and again on this particular map?

The original inspiration to run these alternate histories came from Wyatan. He decided to rerun the Season Four games 20 times each and publish the results. The objective in his words was twofold:

- See how random the prediction game actually is. There's a natural tendency when your predictions come true to go "See! Told you!", and on the contrary to dismiss the result as a mere fluke when things don't go the way you expected them to (pleading guilty there, Your Honour). Hopefully, with 20 iterations, we'll get a sense of how flukey the actual result was, and of how actually predictable each game was.

- Get a more accurate idea of each leader's performance. Over 6 seasons, we'll have a 75 game sample. That might seem a lot, but it's actually a very small sample, with each leader appearing 5-10 times only. With this much larger sample, we'll be able able to better gauge each leader's performance, in the specific context of each game. So if an AI is given a dud start, or really tough neighbours, it won't perform well. Which will only be an indication about the balance of that map, and not really about that AI's general performance. But conversely, by running the game 20 times, we'll get dumb luck out of the equation.

Wyatan did a fantastic job of putting together data for the Season Four games and I decided to use the same general format. First I'll post the resulting data and then discuss some of the findings in more detail. Keep in mind that everything we discuss in these alternate histories is map-specific: it pertains to these leaders with these starting positions in this game. As Wyatan mentioned, an AI leader could be a powerful figure on this particular map while still being a weak leader in more general terms. Now on to the results:

Season Six Championship Game

Game One | Game Two | Game Three | Game Four | Game Five

Game Six | Game Seven | Game Eight | Game Nine | Game Ten

Game Eleven | Game Twelve | Game Thirteen | Game Fourteen | Game Fifteen

Game Sixteen | Game Seventeen | Game Eighteen | Game Nineteen | Game Twenty



(Note : "A" column tracks the number of war declarations initiated by the AI, "D" the number of times the AI is declared upon, "F" the points for finish ranking, and "K" the number of kills.)

The Season Six Championship was one of the more surprising games that I can recall watching for AI Survivor purposes. Everyone was expecting Mansa Musa to get dogpiled due to his high peace weight and that Churchill would be irrelevant since he appeared to be noticeably inferior to the other AI personalities. Instead, we would up with a bizarre match where Mansa Musa largely stayed out of warfare entirely and Churchill conquered first Catherine and then Pacal en route to being the score leader topping the field. This felt like a wacky result and the alternate histories confirmed that yes, this was an exceptional outlier result that bore little resemblance to how the competition was "supposed" to go. Most of the games looked more like this:

Mansa Musa was RELENTLESSLY attacked, over and over again, without fail across the alternate histories. That particular image with everyone at war with Mali was from Game #12 but it was nearly as bad in many of the other alternate histories as well. Mansa was invaded 75 times across the 20 games for an average of nearly four times per game; Churchill was the next-closest at 43 times attacked and no one else reached even 25 invasions. This included the truly preposterous Game #20 where Mansa was attacked NINE different times before he finally suffered a late elimination on Turn 311. The Malinese were eliminated 17 times in 20 games and this was very much not a fluke as Mansa suffered the First to Die fate 13 additional times. To his credit, Mansa Musa did manage a first place and a second place finish in those three games where he wasn't eliminated but the diplomatic pressure was simply overwhelming in the vast majority of matches. As for Churchill, we expected him to be outclassed by the rest of the field and that's exactly what happened across the alternate histories. He was an utter non-factor across the 20 replays of the map, never taking first or second place and never being in a position to contend for the victory. I failed to see anything even remotely like the strong Churchill in the actual Championship game which suggests that this was a wildly unlikely outcome.

So what happened to throw the real Championship off kilter in such a strange fashion? Having seen how the map "normally" played out, I can identify two main turning points. The first was a series of mutually destructive conflicts between Huayna Capac, Pacal, and Cyrus that dragged all of them down. Huayna Capac and Pacal were the two strongest leaders on the map, however in the actual Championship they clashed in an inconclusive early war that slowed both of them, followed by Cyrus then attacking Huayna Capac in another wasteful conflict. That was followed by a second Incan vs Persian war later which was equally inconclusive. The fact that none of these three low peace weight leaders found themselves at war with Mansa Musa or Churchill was extremely unusual - normally some combination of these three plus Catherine worked together to eliminate their high peace weight rivals. Instead, they found themselves at one another's throats and warred to no purpose at all.

Meanwhile, the other turning point involved Catherine. She was the score leader coming out of the landgrab phase only to suffer the exceptionally bad luck to declare war on Mansa Musa on the same turn that Churchill declared war on her. This trapped the Russian leader in a two front war, and with the other three leaders stuck warring with one another, there was no help coming for Catherine. She was the First to Die in the Championship game which was another exceptionally unlikely event, something I saw only twice in the 20 map replays. Thus Churchill and Mansa swelled in size by consuming Catherine's lands in a fashion that simply did not occur elsewhere, which combined with the self-destructive behavior of Huayna Capac / Pacal / Cyrus opened up an opportunity for Mansa to take home the trophy with his Cultural victory. I'm glad that Mansa was able to win a season of AI Survivor since he was absolutely a deserving victor; fortunately we narrowly avoided Churchill taking him the crown which would have been truly absurd. (Churchill was one of the weakest AIs in his playoff game and then the absolute weakest in this Championship game - he was incredibly lucky to put up the results that he did in Season Six.)

The more typical games were essentially a contest between Huayna Capac and Pacal for supremacy, more or less what the community had been expecting going into the Championship. Huayna Capac was the best all-around AI in the field and once again demonstrated his mastery of the AI Survivor format. He won eight victories and could have had even more if he hadn't suffered some bad luck in several of these matches (i.e. his true strength level was likely slightly higher than what this table indicates). Huayna Capac had the most kills, the lowest elimination rate at 10%, and was never First to Die. When he didn't win, he often found himself in second place since the Incans were inevitably one of the score leaders contending for the victory in each game. As for Pacal, he also won eight games but did so with a much more narrow strategy. Pacal basically went for a Cultural victory in every game, often running severe risks by turning on the slider at an early date when he lacked basic endgame techs. He won by Culture twice without having Rifing tech... and also saw a couple of attempts collapse when his cultural bluff was called by someone else. There were some awesome Huayna Capac vs Pacal clashes where the Incans narrowly averted a Mayan cultural victory, especially in Game #13 where Huayna Capac took one of Pacal's Legendary cities when it was sitting on 49k culture two turns before the victory was about to arrive. Pacal's total focus on culture yielded him some wins that he arguably didn't deserve but this came at a cost: he had few kills and only a single second place finish. Thus while Pacal won just as often as Huayna Capac, it was all-or-nothing on the Cultural attempts for the Mayans without any kind of backup plan.

The final two leaders, Cyrus and Catherine, were also pretty much what the community expected: major contenders for a runner-up spot but not leaders strong enough to have a realistic chance at victory themselves. Cyrus had seven second place finishes while Catherine added a further half dozen, with both of them tagging along behind either Huayna Capac or Pacal in a bunch of different matches. They both had some victories, Catherine with a pair and Cyrus with a single victory, but a closer look reveals that these were basically fluke results. All three of their wins were Diplomatic via the United Nations due to Pacal building the wonder at an early date in many of these games. These were victories that probably wouldn't have been achieved if the games had played out to a normal finish, such as Catherine's victory in Game #3 coming with Huayna Capac's spaceship mere turns away from landing and Cyrus' win in Game #11 a truly baffling result that came out of nowhere. I'm glad that the actual Championship game didn't end in this fashion or we might have had a riot on the Livestream! Anyway, these were solid leaders that could score kills and be effective while lacking the truly ridiculous economies that powered Huayna Capac and Pacal to their respective victories.

Now for a look at the individual leaders:

Leader Summaries


Huayna Capac of the Incans
Wars Declared: 53
Wars Declared Upon: 24
Survival Percentage: 90%
Finishes: 8 Firsts, 5 Seconds (50 points)
Kills: 17
Overall Score: 67 points

Huayna Capac was the favorite in the picking contest going into the Championship game and he backed that up with the most consistent performance across the alternate histories. With better luck he would have been celebrating his second crown as the first repeat winner of the competition. Huayna Capac's best path to victory came from taking part in the inevitable partition of Mansa Musa's territory and then afterwards out-teching the rest of the bunch with his superior economy. He partnered well with both Cyrus and Catherine in different games, especially when he was able to get a religious alliance with one or both of the leaders on the southern half of the map. The Incans were also surprisingly aggressive in the alternate histories, with the most total offensive wars in a narrow edge over Catherine. I mentioned above that Huayna Capac was unlucky in several of the early games, losing to Catherine's Diplo victory in Game #2 and then Cyrus' Diplo victory in Game #11, as well as getting cheesed by Pacal's no-Rifling tech Cultural victories in a couple of other games. I was thinking that I was going to have to write about how Pacal was the top scorer but only due to small sample size and that the Incans were clearly the stronger performers. Fortunately this ended up rectifying itself over time as Huayna Capac won 6 of the final 9 alternate histories to wind up more or less where he should have been. If you're reading this report then you already know the story: Huayna Capac is really strong with the game settings that we use and he proved it yet again in these alternate histories.


Pacal of the Mayans
Wars Declared: 25
Wars Declared Upon: 20
Survival Percentage: 60%
Finishes: 8 Firsts, 1 Second (42 points)
Kills: 5
Overall Score: 47 points

Pacal essentially roleplayed as Gandhi in the alternate histories, avoiding conflict as much as possible while repeatedly chasing after Cultural victories. He was involved in the fewest wars by a wide margin, only 45 total wars in 20 games, and never saw a single conflict in Game #14 (which was unsurprisingly a Pacal Cultural win). The Mayan leader had the simplest gameplan possible, turning on the culture slider at some point in the Renaissance or Industrial era and then hoping to avoid warfare for the rest of the game. This worked surprisingly well thanks to Pacal sharing a low peace weight with most of the leaders and the Championship game lacking any of the truly insane AI personalities like Shaka or Montezuma. Some of these Cultural attempts made for wild rides: Pacal narrowly took the victory in Game #1 thanks to Cyrus attacking Churchill at a timely moment and winning two other matches (Game #7 and Game #14) where he lacked Rifling tech without ever getting attacked. He was also stopped at near-successful Cultural attempts in Game #13 and Game #15, both times by Huayna Capac, with these luck factors roughly balancing out across the 20 games. As mentioned above, Pacal's obsessive focus on culture meant that he had few kills and only a single runner up finish to his name. Thus Huayna Capac wound up being the stronger and more consistent AI leader via our scoring system even though Pacal tied him for the number of outright victories. Pacal only did one thing in these games but he did it very well indeed: seven different Cultural victories that were all achieved before Turn 300!


Cyrus of Persia
Wars Declared: 36
Wars Declared Upon: 21
Survival Percentage: 85%
Finishes: 1 First, 7 Seconds (19 points)
Kills: 15
Overall Score: 34 points

Cyrus and Catherine were the two leaders that made up the second tier of the Championship game, with Cyrus coming out slightly higher than his Russian rival. The Persians were strong enough to hang around for the runner up spot a bunch of different times while lacking the economic heft to claim an outright victory. (Whether it was Huayna Capac or Pacal, the two Mesoamerican leaders both won blisteringly fast victories in most of the alternate histories.) For examples of this, Cyrus was the score leader in both Game #9 and Game #15 but in each case he wasn't able to reach a victory condition before the superior economies of first Pacal and then Huayna Capac made it over the Cultural finish line. More frequently, Cyrus tagged along as the junior partner behind one of those two leaders as they marched to victory. For whatever reason, Cyrus had unusually good luck in scoring the "last hit" to claim kills and his kill total is somewhat exaggerated above where it should be. However, he still grades out higher than Catherine because the Russian leader lucked into two Diplomatic victories that artifically inflated her own scoring. Cyrus similarly had his own lucky Diplomatic victory without which he wouldn't have claimed the top prize at all. Anyway, Cyrus was noteworthy for randomly claiming a lot of kills and for having an excellent survival percentage. Sometimes simply being alive leads to a decent number of kills and second place finishes as other opponents are cleared from the board.


Catherine of Russia
Wars Declared: 48
Wars Declared Upon: 20
Survival Percentage: 65%
Finishes: 2 Firsts, 6 Seconds (22 points)
Kills: 8
Overall Score: 30 points

Catherine was in a similar position to Cyrus while performing just a little bit worse, largely thanks to the fact that she was eliminated about twice as often. Cathy found herself at war with Mansa Musa in almost every game and this left her vulnerable to a potential 1 vs 2 situation if another leader hopped into the fighting on the other side. Some of Huayna Capac's strongest games took place when he rolled through Catherine and annexed the Russian territory for himself. In Cathy's better games, she was the one taking over Malinese territory and using it as a springboard up to the top spots in the field. Unlike so many of the other AI Survivor games that we've watched, Cathy's expanionism was never good enough to overcome the economic strength of Huayna Capac and Pacal. I guess it was a bit like her playoff game this season where Mansa Musa's teching was similarly too powerful to overcome. Cathy was often a strong competitor while never truly being a threat to win the game outright - her Diplomatic victories were lucky breaks which wouldn't have been wins without Pacal building the United Nations for her. I suspect that if we ran 100 alternate histories we would only see a couple of additional Catherine Diplo victories and that this was small sample size bias at work. She was a great second banana while seemingly always stuck in the Robin role to someone else's Batman.


Mansa Musa of Mali
Wars Declared: 15
Wars Declared Upon: 75
Survival Percentage: 15%
Finishes: 1 First, 1 Second (7 points)
Kills: 1
Overall Score: 8 points

This poor guy. The alternate histories were rough going for the actual winner of the Season Six Championship as the diplomatic vulnerabilities that he avoided in the real match came back to haunt Mansa again and again. There's very little that any leader can do when they face two, three, four, even five opponents at the same time in game after game. Mansa always put up a dogged defense in these alternate histories but the end result was almost always the same, with Mali suffering the First to Die fate in two-thirds of the alternate histories. The timing was eerily precise as Mansa died between Turn 150 and Turn 180 over and over again. However, Mansa Musa is still a great leader for AI Survivor and he managed to make the most of the few chances that he did get. In Game #4, Mansa was left alone for once and managed to solo conquer Catherine en route to a very convincing Domination victory. He might have been even more impressive in Game #17 where he was the top AI on the scoreboard despite getting invaded six different times; those relentless attacks knocked Mansa into the runner up spot as he couldn't stop Pacal's Cultural victory while under constant assault. Overall, the alternate histories demonstrated a more realistic outcome for Mansa Musa, an excellent AI leader who was thoroughly screwed over by his diplomatic surroundings.


Churchill of England
Wars Declared: 26
Wars Declared Upon: 43
Survival Percentage: 40%
Finishes: 0 Firsts, 0 Seconds (0 points)
Kills: 3
Overall Score: 3 points

The general perception going into the Championship game was that Churchill was a weak AI leader who didn't belong in this field. The alternate histories revealed that... Churchill was most definitely a weak AI leader who didn't belong in this field. Don't be fooled by his remarkably successful performance in the actual Championship game, that was an absurd outlier result which was never repeated in future playthroughs of the same map. Churchill had a subpar diplomatic situation (if nowhere near as bad as Mansa Musa) and lacked the leader traits or unique units/buildings that benefited his rivals. I'd like to talk about the games where Churchill had success on this map, only he kind of didn't have any successful games at all? Just the actual Championship game that we watched on Livestream. Otherwise he never had a first or second place finish and he was never among the scoreboard leaders at any point in time. The best that he could do was pick up a few random kills here and there for a measly 3 points in our scoring system. If there was ever a leader who gave a misleading impression of strength in a season of AI Survivor, it was Churchill in his last two games of Season Six. This guy is completely mediocre, don't let the results of a single game fool you!

Conclusions

The Championship game for Season Six capped off a year that seemed to have a lot of weird results. Outside of the three playoff games where things largely ran according to plan, we had game after game where things played out completely differently from the typical case in the alternate histories. Whether it was Pericles disappearing from Game One (despite winning 15 alternate histories!), Pacal taking first place in Game Two while scoring literal ZERO points in the alternate histories, or Victoria settling 17 cities unopposed in Game Eight, this was a bizarre year that threw the picking contest into chaos. I suppose it was fitting that we had a ridiculous Championship ending as well that capped off with Mansa Musa claiming the overall trophy. Fortunately we have the alternate histories to let us know that no, we aren't crazy, it actually does matter that Mansa Musa has a peace weight of 9 in a field of low peace weight opponents. He might avoid diplomatic disaster in a game or two but the average case wouldn't turn out nearly as favorable.

Thanks as always for reading, I hope you enjoyed this look back at the Championship from Season Six!