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Fear leads to anger. Anger leads to hate. Hate leads to suffering. Leia dreams of Luke's fall to the Darkside.
Fear
She sees Luke running from a shadow. Fear is in his eyes. She wants to help him but can do nothing. He keeps running but eventually the shadow catches up to him. A gloved hand reaches out and grabs him pulling him into darkness. As darkness begins to swallow him he becomes terrified. The darkness swallows his legs and works its way up. As it begins to swallow his face his eyes change from their beautiful blue to a terrifying yellow and then he is gone.
Anger
She sees someone in black robes killing Rebel soldiers. She senses much anger in him. The figure turns around to face her and she screams. It's Luke his eyes Yellow with anger. He approaches her but more rebels fight to protect her. Luke slaughters them without second thought. She runs trying to stay calm. She trips and he approaches her, and she screams.
Hate
She's in the throne room of the Emperor. She stands before the Emperor with Luke standing behind her. The Emperor stands up and attacks her with lighting. She crumbles to the ground yelling in pain. She looks back at Luke his anger reaches a boiling point and his eyes are full of hate. He attacks the Emperor with all of his hatred and strikes him down. He turns to her, and she sees so much hatred in his eyes that it causes her to black out.
Suffering
She see him alone in a dark void. He's on his knees and seems like he crying. She approaches him and puts her hand on his shoulder. He looks up at her his eyes full of suffering. No words are exchanged but no words are needed. She can sense and see his suffering and she wants to help him. The shadow returns and she tries to run but he grabs her arm and won't let go. He pulls her into the shadow to have her share his suffering and as the darkness swallows her fear fills her eyes.