Note that this screenshot is annotated. The issue is with the leftmost planet. For clarity, when I say "strategic resource", I mean "Water, Biomass, or Metal" (what I previously guessed in a previous bug report as being "Ice Cubes, Marijuana, or Corinthium"). I say this to specifically distinguish them from the common resources: Production, Combat, Wellness, Science, and Exploration.
I wasn't taking careful notes during my game (I never do), but what I THINK happened is that a strategic resource got added to this planet by an Exploration event, and THEN I added an Extractor to this planet, and THEN a Technology added Biomass to a different planet, and THEN I noticed that this planet had an Extractor, but no strategic resource.
I can't be 100% certain of that sequence of events. What I can tell you with absolute certainty is that I did NOT build an Extractor on a planet that lacked a strategic resource at the time of the Extractor's construction. A strategic resource was there when I built the Extractor, and now it's gone.
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As a side note, I am enjoying the game, despite the growing pains. 8P
