From the strategy guide written by Stefan Sasse
Twilight Imperium 3 is not only a game in which you have to understand the mechanics and use them to your advantage but in which you also have to understand your fellow players and exploit this knowledge to your advantage. Are your fellow players defensive and do they like to turtle, massing up their fleet for one climactic battle? In this case, you have easy going. Do nothing that provokes them, build and tech up a similar fleet and bubble victory before they want to start their battle. Are your fellow players very aggressive and do they tend to attack often and early? Then it depends whether they do so just for fun or if they actually want to accomplish something. People that attack just for the sake of attacking, wanting to stack resources and influence and bring a lot of carnage to the galaxy you can’t reason with. They will attack, and it doesn’t matter if it hurts their game or not. Try to stay away from them and to form alliances against them, crippling their ability to hurt you a lot. Players that attack vital spots, make retreats and attack elsewhere in an overall plan are much more of a threat. Normally, they know what they want, how to achieve it and how to hurt you. If the attack is just to their benefit, you may perhaps even yield the object of his desire – like if he wants to take MR and you already scored the corresponding PO. With most of these players you can be sure, though, that they won’t fight just for the sake of it and pull both combatants down while the others score their way to victory.
Generally it is important that you have friendly relations with at least one of your direct neighbors. This allows you to concentrate your forces where you need them instead of having heavy vigilance along every border. Of course, Stalin had to have thought something similar before Hitler attacked him. In the case of trusting other players, you can only build on experience. If you play often with the same group, you can even throw your game away in case of a treasonous backstab that prevents you from winning anyway and drag the backstabber with you to send a clear message that it is not wise to mess with you. Some may dismiss this as metagaming, but I say it’s allowed.
Same goes for sometimes doing unfavorable things like holding truces and treaties that don’t help or even hinder you. If this helps you to get the trust of your fellow players, it’s worth the effort oftentimes. Remember that the other players too will see that you are trustworthy even if they are on the opposing side. Next game the fronts might be reversed. When every player “knows” that you are a dirty backstabber and are not trustworthy, they won’t ever really deal with you unless they are stupid. Be reasonable. No one can demand that you lose a game holding a stupid truce, but if you can win a game holding it even if this means some inconveniences in opposite of the easy way of breaking it, you should go for it. Your reputation will be the better for it.
But how to secure friendly relations with a neighbour? Most powerful thing is giving him a high trade agreement. Of course, not all races are able to do this because they simply have only 1- value trade agreements. But if you are playing Hacan or Jol-Nar or something like that – resist the temptation of trading your 3-trade agreements against other high value trade agreements. Give them to neighbors with aggressive races like L1z1x or Letnev or something like that. Getting these juicy trade goods every round is a very high incentive not to attack you, and you can even use metagaming should they break it and conduct a “no trade” policy on them in the next game to teach them manners.
Now, you are not always able to play nice. Sometimes, you will have to break agreements yourself. If you do this, it is important not to do this while displaying all the fun it is backstabbing an opponent and former friend and seeing their weak flank crumble, but to express your deep regret and to be perfectly reasonable. Never stop explaining your actions and finding logical reasons to do what you are doing. Oftentimes you can talk your opponent into accepting that the move you just made was necessary, and you didn’t have a choice. Promise him that you will pull out as soon as possible, and even promise compensations. You will be surprised how many people will forgive you blowing away half their fleet when you give them 3 trade goods in return as amends. It’s utterly stupid, but it works more often than not.
That is because most players are not able to measure the correct relationship between losses and wins. If the “destroy three ships” public objective is and there is a crappy fleet of two destroyers and a cruiser around, it is easy game to destroy it. You will be surprised at how often you can soothe your opponent by telling him in advance you want to destroy it for the sake of the public objective and you are willing to pay him a trade good for it. Of course, you tell him right before you do the action, so he has no possibility to react to it anyway, but it looks honest. Announcing a backstab is surprisingly effective in terms of reputation. You offer him one trade good, he perhaps insists on two, and you still have only paid half the worth of the fleet and fulfilled a public objective! Deals like that can often times be made regularly.
I already addressed the use of Diplomacy II’s Secondary for planet tradeoffs, especially with players you have a trade agreement with since this isn’t broken by that. But there are other possibilities. Many players want to avoid wars with the nice guy you are posing as because there always is someone around stacking an army and looking aggressive (a task you help him with, see below). Surprisingly, it is often possible to broker deals like “you empty planet X so I can annex it and so I don’t have to invade the system and take out the fleet in orbit.” Many players will think they are actually on the winning side of such a deal, having avoided a conflict that might hinder their plans.
Back to the point of measuring loss: many players tend to overrate trade goods. Oftentimes, these get stacked for no better reason than having them, and then a gigantic fleet is produced without a clear concept what to do with it. It is better to sacrifice some trade goods in order to reach a long-term goal. The guys with the big army seldom win; frequently it’s those sneaky guys that are attacked and nearly – but only nearly – wiped out in the last round. Losing a planet means not only that you forego the income for this round, but also for the next when you are able to take it back then (unless you have Nano Technology). If someone wants a planet from you, try to persuade them only to take it after you have exhausted it. Oftentimes, you can use this as a bargaining chip as well and offer to wait for exhaustion instead taking it immediately – other players will then think they have actually won something.
So, how to counter such stuff? You need information. This is often more difficult than you imagine. It’s a boardgame, right? Except for the hand of cards, all information is open, right? Yes, of course. But there is a thin line between being allowed to know all that stuff and actually knowing it. Many offensives failed because the attacker overlooked an important tech researched by the other player who, of course, didn’t remind you he had. Always know what the other players have and try to figure out what they are up to. You can then measure if a certain offer of theirs hands them victory or if it is unimportant. Try to remember important action cards played so you don’t have to worry about them anymore.
Another diplomatic aspect of the game are the Political Cards. The political cards vary very much in effect; some of them don’t influence the game much, some have gamebreaking effects. Some affect all players equally, some fuck up just one player a lot. The latter variant is an open declaration of war. The problem with these political cards is, that one player HAS to be elected. Whoever votes first has a bad spot here, because he has to reveal who he hates. If you are not sure if you can get a majority against a given player, it might be wise to abstain so you don’t piss off someone for no better reason than he was the first you thought of. Voting on agendas is also a great time to bargain some favors. “Closing the Wormholes” is on, but you have none in your proximity? Sell your vote to the highest bidder. Agenda votes are usually very situational, so it is difficult to give general advice. If you are starting to sell votes, you should make this an open thing. Announce from the start that if an agenda does not handicap you you sell your votes to the highest bidder. Many people will accept an honest position like this. But be certain that you don’t double-cross people here – trustworthiness is key.
Yet another roughly diplomatic aspect is stalling. Sometimes, you want all your enemies to pass in order to perform an action they are not able to react to. In this case, you need to stall. This essentially works only when you have more command counters available than he does. When someone begins to take seemingly useless actions like activating systems at the other end of the map for no reason, he is most likely stalling. If he has more command counters than you, he can force you to pass at some point and then take one or several actions you don’t have a chance to respond to. This is mostly done to prepare a bubble victory or for attacks on important systems; in the latter case the staller then is often speaker. This way, he brings his force into position after everyone has passed, chooses Leadership the following round and attacks with his first action. If you think that someone is stalling, alert everyone and try to determine what he’s up to so you can prevent it from happening before it is executed entirely. You might even try to calculate if he will be able to stall you and how many actions he’ll have left by then, but remember that not only Tactical Actions can be used for stalling, but also certain action cards or racial special abilities.