Doesn't radiation this high imply that the entire city stops working? Is this an especially strong solar flare?
And I guess I am surprised that the soldiers are not at least somewhat hardened against radiation. Implies an EMP weapon would be super effective against Unity military.
The city could have an auto-off function to disable their less shielded electronics prior to solar flares. Seems likely if the star they orbit has them regularly, or if they're able to predict them.
I figured their suits were at least partially biological in nature, given their wide range of abilities and seemingly skin-tight fit. The suits die from the radiation burst and their inhabitants suffocate under the unaided heavy-mode; thus the "turning blue".