Shipgirls whom the Guardian Deity has fallen for can transform into Kai-2 after their gauge charges up. Guardian uses the same first two kanji as "naval base". Which was the reason for all the earlier blind-idiot translations of naval base as "guardian office".

...but a price exists; something will be lost in exchange for this power.

Do you still want to become Kai-2, even after hearing that?

Take a good look over there.