The answer is easy, your GOOP storage tanks are full and your mules being smarter than you are realise that hauling up any more stuff is a waste of time. If you simply must blow off steam, your rangers can be ordered to kill attacking creatures but woe betide you if the Ethereals find out. Forgetting their peaceful nature, they'll reduce your carefully constructed base to rubble in a trice. Gene Wars comes with 24 missions of which I have completed the first 10. Ok, that doesn't sound too impressive but I have sweated blood getting this far.
Some missions are a doddle, easily completed at the first attempt.
Others bring this heady progress to a halt with a shattering crash. I have taken weeks to get past one or two of the more difficult missions. Ah, but there's the rub. It may have taken me weeks but something kept me coming back to the game when I could have been more profitably engaged in sorting out my collection of early Egyptian cat flaps. Yes, Gene Wars has grip and I at least was firmly enmeshed by its attractions.