[Alneyan]

A small thing perhaps worth mentioning: red nebulaes grant you the best kind of cloaking, which cannot be bypassed by *any* sensor. This can be used to help your natural paranoia, or to have a nice secure system when striking against another Empire.

On the topic of game mechanisms: happiness is one of the most important factors of your Empire, and keeping it as high as possible should be one of your priorities. Happiness works as follow: all your planets have an happiness value (from 0 to 1000) expressing the number of unhappy people on this planet. If you have an happiness value of 0, nobody is angry on this planet, whereas a value of 1000 means everyone is out asking for your blood. These values are expressed in tenths of percent, so 540 means 54% of the inhabitants of this planet are unhappy. From the Happiness.txt file, the various levels of happiness are as follow:

Population Anger (in %) Descript. Resource Modificator
75 - 100 Rioting 0%
60 - 74 Angry 80%
45 - 59 Unhappy 90%
30 - 44 Indifferent 100%
15 - 29 Happy 110%
0 - 14 Jubiliant 120%

So what modifies happiness? The following means can be used to reduce your population anger values, thus improving your happiness. Note that most of the values are given for the Peaceful happiness type, by far the most common. For other happiness types, please replace the numbers as needed.

*Empire wide positive changes:
- Colonising a planet decreases unhappiness by 1% per planet colonised.
- Likewise, capturing an enemy planet decreases unhappiness by 3% per planet captured.
- Enacting certain treaties (Trade Alliance and above for peaceful) decreases unhappiness, from -2% for a Trade Alliance to -10% for a Partnership. This bonus is only applied when accepting the treaty, regardless of any previous treaty you had with the particular Empire.

*System wide positive changes:
- The Urban Pacification Center, the Fate Shrine and the Temporal Vacation Service improve happiness within a whole system. At levels III, the UPC and the Fate Shrine reduce population anger by 3% (a value of 30) per turn, and the Temporal Vacation Service reduces unhappiness by 6% every turn.
- Having ships in a system decreases unhappiness by 0,3% per ship. Having a big fleet within a system is thus an effective way of quenching unrest.
- Winning a battle in the system decreases unhappiness by 2% per battle won.

*Sector or planetary changes:
- Winning a battle over the sector decreases unhappiness by 5% per battle.
- Every troop on a planet decreases unhappiness by 0,2%, regardless of the strength of the troop.
- Friendly ships decreases unhappiness if they are over the planet(s) in question, by 1% per ship.
- Building ships and facilities should decrease unhappiness by 0,5%, which only affects the planet in question to the best of my knowledge (this bonus is fairly weak, and I have yet to see it play a major part, so I gather it is only planet wide).

And now the more annoying part, why you are losing happiness. It goes as follow:

* Empire wide happiness losses:
- Losing a planet (where the planet is destroyed from orbit) increases unhappiness by 5% for the whole Empire. This is the main reason why happiness collapses if you are fighting a defensive war (where your planets are being glassed). Losing your homeworld thus increases unhappiness by 10%, which may or may not stack with the regular happiness loss.
- Losing a ship increases unrest by 0,1% per ship lost. I believe it applies to the whole Empire, but may be wrong on this one; feel free to correct me if required.
- Having a planet captured increases unhappiness by 3% per planet captured.
- Specific treaties lower your happiness, such as War, Non Intercourse, and Subjugation/Protectorate when you are the dominated party. Again, this is only for the Peaceful happiness type.

* System wide happiness losses:
- The presence of enemy ships increases unrest by 0,5% per ship.
- Losing a battle in the system increases unrest by 2% per battle.
- Every ship lost in the system increases unrest by 0,2%.

* Sector or planet happiness losses:
- Losing a battle in the sector increases unhappiness by 5%, while having a battle without a clear victor increases unhappiness by 1%.
- Every ship in the sector increases unrest by 0,8%.
- Every one million settler killed increases unhappiness by 0,1%.
- Enemy troops on the planet (in the case of long ground battles) increases unrest by no less than 20%.
- Having a plagued planet increases unrest by 20% as well.

The following can improve or decrease happiness:
- Points above 100 in the Happiness characteristic gives you a small increase of happiness for your whole Empire, whereas points below 100 decreases your global Happiness. Note that this effect has little impact on the game, because of the Natural happiness decrease.
- The Natural decrease is of 2% every turn, regardless of whatever else may happen. This will push happiness towards the Indifferent level if you are between Jubilant and Angry, by 2% every turn. So if you have a planet with a Jubilant status, this will be a decrease, whereas it will actually increase happiness for an Angry planet. Natural decrease does not allow you to "undo" a riot on a planet however.

Since the 1.91 patch, there is an effective cap for happiness changes each turn. This is set at 20%, either positive or negative, and means you cannot increase or decrease unhappiness by more than 20% every turn. So if all your planets were Jubilant, you could not fall immediately to Riots in a single turn (you would need between four and five turns for it to happen). Before the 1.91 patch, this cap was indicated in full percents, and so was set at 200% (twice as much as the maximum anger value), hence resulting in immediate massive riots if you had lost enough planets in a single turn.