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How does enemy progression work?
I am planning on starting a new game soon, and thought I'd wait a while longer this time between completing the different plot-advancing objectives, so that I can exp up my soldiers and build out my base at a more comfortable rate. This is obviously based on the assumption that the aliens don't scale up their invasion and throw in more advanced troops unless I advance the plot, and I'm not at all sure of this.
I'm pretty sure that I won't encounter ethereals until after building the hyperwave relay and shooting down the cloaked ship, since the encounter with the first ethereal is quite intimately tied up with the plot, and the first time I encountered cyberdisks was when assaulting the alien base, coincidence or not. But how does it work, might I encounter muton elites before capturing my first sectoid if I put it off long enough?
