Did anyone playtested if a hidden nation unit causes diplomatic tensions? My idea was to use pre placed hidden nation units in a scenario to trigger tensions between different civs. I know that I can use the favored/hated government, but I would like to have another option. If the answer is yes I would like to know 1. If it matters how many hn-units there are? 2. If the hn-units have to destroy other units to cause tension? 3. how long do the tension last? 4. Does the ai "know" who to blame for? 5. Does the hn-unit need to be in the others civ's cultural borders or can it be anythere? 6. Can the hn-unit be an artillery and if yes does it need to do serious damage to cause tensions? How does the ai handle these units? Would this work: A civ has a special recource in one of it's cities. This recource let them build a building only in this city when they reach a special tech. The building produces a special unit that is unmoveable, has a (weak) bombardment, is destroyed after one use (like cruise missiles are), and has hidden nationality. Via the citieplacement and the units range I could set up a scenario in that one civ would start a "cold war" against another civ withe a certain tech level, and possible end it with another (by making the building obsolete). Another Idea I head was for a Europe1850-19xx Scenario to trigger wars for Alsace-Lorraine between Germany and France. A preplaced "Wonder" in let's say Strasbourg gives the French a unmoveable hidden nation Artillery every soandso turn. By the time they get a nice stock of this unit and the Germans get pissed of more and more, till they start a war. If the Germans are able to take Strasbourg an make peace the Wonder will start producing the unit for the Germans and France will be pissed of by the time and start a new War. This would only end if the Wonder goes obsolete and the remaining Units are updated to something else or if one of the civs conquers enought terrain that the "hate unit" can't reache any target. Well, if anyone tested this already it would be really nice if you share your knowledge.