The silver, transparent cage that Florita used to trap Krythorion and Zalga was one of her Authorities: Dark Contract.
Under its effect, she could trap anyone within a cage, forcing them into combat with her. The only way for a trapped opponent to escape was by killing Florita, and similarly, Florita could not leave the cage without killing her opponent.
The Dark Contract functioned as an equal exchange, making the cage a life-and-death arena from which neither could escape without victory over the other.
Normally, under the effect of the Dark Contract, no one could interfere in the battle between the opponents trapped inside.
However, Florita's situation was somewhat unique. Firstly, she had been summoned to the Azragoth World under the effect of Evan's authority: Realm Guardian, and could be considered his summoned unit, representing him.
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