I Love this chapter It's almost flawless. only missing the funny storyline quest, weapon and shield color changing stuff from the first one, Maybe add some Description to Artifacts like for UO defender "This Shield is crafted from another world bla bla bla..." and a name changer.
how to farm rare units ? i got only tesla as the rarest unit in my base
does the 1.5M (5% rare drop rate) upgrade stacks if I build another Tech center
 "Arkandian Explorer"){kind=icon}
 "Enigmata: Stellar War"){kind=icon}