Croix had invested almost all her Path traits into "Shadow Affinity" during her advancement.
The first level of Shadow Affinity only made her less noticeable when she was in the shadows, or helped reduce her presence when her face was obscured by darkness.
Starting from the second level, Shadow Affinity began to interfere with reality.
After Croix enhanced her Shadow Affinity to the second level, she could infuse her daggers and arrows with the power of shadows, because the strength of shadows had already penetrated the mystical skill of "Assassination."
By the third level, the power of shadows had infiltrated her profession's ability of "Stealth."
Now she could completely vanish into the shadows.
