Yes, I believe there are 5 stages if you want to call them that of zone control.
Neutral- No faction is winning, neither 'store' will sell temp powers
+1 Blue- Heroes are winning, the 'store' will sell tier 1 temp powers (emp glove, webnades, raptor pack, jaunt initalizer,low G pack)
+2 Blue- Heroes are firmly winning the zone, the 'store' will sell tier 2 temp powers (cryonite armor, stealth suit, stun grenades, IR goggles)
+1 Red- Villians are winning the zone- Store will sell tier 1 temps
+2 Red- villians are winning the zone- Store will sell tier 2 temps
Sorry I am not sure about the tiering of villian temps- I know they get all the travel ones the heroes get as well as Kinetic sheild, arachnos mace, venom grenade, smoke bomb.
I was more of meaning the percentage bar at the top. Has there ever been a time where heavy fighting (or the zone being empty...) the bar has swung all the way to one side?
I am fairly sure that the 'hot zones' battles are random. So yes at times one faction will win the zone even if there is no one in Sirens.
Is it possible to completely overtake the zone control for either faction?
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Mission Architect Handyman