I see on the mex upgrade tooltip that it costs 9mass/sec.
I pause everything so that my mass consumption is 0.
I hit the mass upgrade button and I see that my mass consumption is now 10mass/sec!
I get an engy to assist the mex upgrade. I see on my engy's tooltip that its consuming 3mass/sec.
Except that I notice my total mass consumption is now 14mass/sec!?
Is there some bug? Do mex upgrades consume +1mass/sec/unit more than they should?