More testing on planet happiness ability:
I built a faciltiy with -20 planet happiness. The planet quickly dropped to angry mood, never below. Then I built one with +10, nothing changed for 10 turns of waiting. I built a second +10, nothing changed very fast. Then I built a third +10, and the mood increased quickly.
This confirms that facilities with the planet happiness ability stack with each other. You can build two of the same facility for double the effect. A negative facility and a positive facility add together, not one replaces the other.
Note that for the system happiness ability, only the best ability in the system is used.
[ August 06, 2004, 19:48: Message edited by: Imperator Fyron ]