Akantha the Deceiver
In order to discover the identity of this enemy, you must obtain the appropriate document. This one is located in Olynthos Fortress, in the building shown on the screen above.
Once you have a clue, go to the Leader’s House. There you must eliminate all enemies in order to be able to get rid of the traitor peacefully. Unfortunately, she will flee from you. Additionally, she will summon many enemies.
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What do you do if she does flee from you? She ran from me and I havent been able to find her since.