most of her life cosma was a happy carefree unicorn, until the day came that changed her life forever….she was walking along the mountain trails with her older sister, blazing trail, enjoying the hike when a rock slide happened, out of no where her sister was swept down the side of the mountain….cosma fearing for her sisters life sent out a distress flare spell and went to try and help her sister
 
afterwards her sister was sent to canterlot hospital….she lost her right hind leg….and had a replacement made by zero zimmer robotics, cosma blamed her self for the injury and wanted to prevent other unseeable accidents ……after some extreme studying and practicing she performed a new spell and earned her cutie mark……the spell of eternal sight…..every possible outcome of every day ..of ever second she sees…..so much she can barely see what happens now….her sight fills her with fear of the world and every pony she meets…she stays in her room, sitting on her bed too afraid to move…..to blink….knowing the most dangerous outcomes could happen at any moment