The following posts were transferred from the COTM 8 Spoiler thread and describe work done to investigate the problem. It was concluded that this did indeed appear to be a bug. AlanH

While playing COTM8 I encountered a strange phenomenon, I was able to buy a lux from Byzantium twice (see this thread (http://forums.civfanatics.com/showthread.php?t=109369).

After I finished this game I went back to my saves to investigate this matter. In 70BC ( http://www.civfanatics.net/uploads8/70BC.SAV) I had the following situation. I had an active contract with Byzantium for incense for 18 more turns.

http://www.civfanatics.net/uploads8/solbug1.JPG
However, our cities were not getting any incense because the trade route was through Babylon and I was in war with them.
http://www.civfanatics.net/uploads8/solbug2.JPG
I was not able to buy more incense from Byzantium, because I did not have a trade route.
http://www.civfanatics.net/uploads8/Solbug3.JPG
IMHO at this point everything was normal.

The next save was at 90AD ( http://www.civfanatics.net/uploads8/90AD.SAV) and I already had this problem:
http://www.civfanatics.net/uploads8/Solbug4.JPG http://www.civfanatics.net/uploads8/Solbug5.JPG

I did not have any other saves in between. So I decided to replay this fragment of the game starting from 70BC (http://www.civfanatics.net/uploads8/70BC.SAV) save.

It seems that the problem started after I built first harbor and I have a hypothesis about what was going on.
My first trade was through Babylon. Since I was in war with Babylon, I was unable to get it. When I built harbor I still was not able to get incense from the first trade, but I was able to establish a new one. And this is what I did. As a result I got this situation.
http://www.civfanatics.net/uploads8/Solbug6.JPG

If anyone wants to reproduce this situation, download my 70BC ( http://www.civfanatics.net/uploads8/70BC.SAV). Open it and rush a harbor in any city. Next turn you will find that you still have a deal for incense, but your cities are not getting any and you can make a second deal.


Later I found another problem:
http://www.civfanatics.net/uploads8/Solbug7.JPG
Iron is clearly connected to Constantinople. Yet, I can sell it to Byzantium:
http://www.civfanatics.net/uploads8/Solbug8.JPG
While playing this game I did not sell my iron to Byzantium. I understood that I missed a good opportunity only now, when I realized that they were ready to give so much (they seem to have iron anyway!).
I do not know how the situation with iron came to live. It may be not a bug if Byzantium is selling their own iron to someone else. But I do not know how to check it. The save at which I notice it is 660AD (http://www.civfanatics.net/uploads8/660AD.SAV).
The closest normal save before this date is 570AD ( http://www.civfanatics.net/uploads8/570AD.SAV) save.

Fixed file links.

While playing COTM8 I encountered a strange phenomenon, I was able to buy a lux from Byzantium twice
I think something went went wrong before your 70BC save. At 70BC you had 18 turns remaining in your alliance with Byzantines which included incense. But you weren't receiving the incense and that should be impossible: either it couldn't be provided in the first place and therefore the alliance deal should not have been possible, or if the incense connection was broken later then the alliance deal should have been cancelled at that time. So I think there's a bug in something which happened before 70BC. Do you have a save file from a bit before making the alliance with Byzantines?

It seems likely that the subsequent problems with weird multiple incense deals are all fallout from that original problem before 70BC.

Iron is clearly connected to Constantinople. Yet, I can sell it to Byzantium:
I think this case is actually ok, nothing wrong. It looks like in 660AD you settled Kutallu 2 near the Byzantine border and that took one source of iron from them. I think it is a safe bet that before this turn they had two sources of iron and they were trading one of them to someone else. After you took that iron they were down to one and had to continue providing it in trade, leaving them with no iron for themselves.

I think something went went wrong before your 70BC save. At 70BC you had 18 turns remaining in your alliance with Byzantines which included incense. But you weren't receiving the incense and that should be impossible: either it couldn't be provided in the first place and therefore the alliance deal should not have been possible, or if the incense connection was broken later then the alliance deal should have been cancelled at that time. So I think there's a bug in something which happened before 70BC. Do you have a save file from a bit before making the alliance with Byzantines?


Sure, I have earlier saves. I will check them in a few hours.
Are you sure that if a trade route is broken then my alliance also should be broken? I am not sure that incense was a part of that alliance deal.
Unfortunately, I do not remember what exactly was going on. I think normally civilizations do not agree to make an alliance against third civilization if none of you in war with that third civ.
Therefore, it is likely that I was in war with Babylon before I suggested an alliance to Byzantium. If so, I could not get incense as a part of this deal, because our trade route was broken.
More likely scenario is that I first sold a tech to Byzantium for incense, then declare war on Babylon and then made an alliance with Byzantium against Babylon. I know it looks stupid: make a deal for a lux and then break a trade route within the same turn.
No matter how stupid it sounds, this kind of behavior does not sound very unusual for my play style. Unfortunately :cry: :lol: laugh through cry
I do not think that it was possible to get incense as a part of that alliance, since the trade route was already broken.
On another hand if I managed to make this alliance before I got in war with Babylon, then it really sounds crazy because this alliance would cancel a trade which was a part of a deal.
I will replay this before 70BC and try different variants in hope to figure out what happened exactly.
I also will post an original earlier save, which is the closest to 70BC.

I also will post an original earlier save, which is the closest to 70BC.

It happened to be 310BC (http://www.civfanatics.net/uploads8/310_BC.SAV) save. It will take me some time to get to 70BC. Hold on.

At 310BC I was buying incense from Byzantium and the deal was for 9 turns.
So I hit enter until the deal was expired. 1 turn before the deal expired I saved a game.
I got a message that we lost incense.
I went to Theodora and made a new deal.
After that my city were still getting incense :confused:
Then I went to Theodora again and ask for alliance. They agreed for 29gpt, but when I looked on F4, there was no incense deal anymore.
In other words I did not succeed to reproduce the problem. But SirPleb is likely to be right that the problem occurred before 70BC.
I will keep replaying this fragment of the game in hope to get it right (wrong actually). I will post here again when (if) I succeed.

I will post here again when (if) I succeed.

Ok, I think I got it. So I first declared war on Babylon and than ask for an alliance and incense from Byzantium:
http://www.civfanatics.net/uploads8/Solbug.JPG
Apparently it looks like the problem is that a trade route is not destroyed after a declaration of war. It get destroyed only after the next turn.

So in order to get my situation download my 150BC (http://www.civfanatics.net/uploads8/Gilgamesh_of_the_Sumerians,_150_BC.SAV) save (please do not take it seriously :eek: , I was just hitting enter to get there). Hit enter, loose incense, declare a war on Babylon, then ask Theodora for alliance and incense in exchange for Theology and you will get a situation very close to what I had at 70BC in a previous post.
After that rush a harbor and you will be able to buy incense for a second time.

Hit enter, loose incense, declare a war on Babylon, then ask Theodora for alliance and incense in exchange for Theology
I also tried this: end turn, declare on Babylon, end second turn. And on the following turn incense is still available from Byzantines. It only becomes unavailable after getting Byzantines to declare on Babylon. It isn't just a same-turn problem. You've certainly hit a weird bug here.

This seems to be a previously unknown bug in the calculation of trade routes. I don't see any possible trade connection to Byzantines after you declare on Babylon - the incense should be off the table then. It is interesting that Byzantines have the Great Lighthouse. That doesn't result in a legitimate trade route since you have no harbors and no land connections except to Babylon. But it is suspicious, I would guess that the bug is related to Great Lighthouse.

Anyway we do now know roughly where things went wrong. Definitely a bug.

Bug investigation posts transferred to C3C Bug Reports forum now that COTM 8 is closed. This post bumps the thread.