There really isn't anything like leveling in the series, and the only girl with what you termed as CR has it as a side effect of her wish. Any and all uses of magic, including the ones that allow them to move their 'puppet' bodies, incurs a corruption cost. When that corruption meter hits MAX, the girl turns into a witch, no save. Accumulated corruption can be removed by placing it into a Grief Seed, and if a Grief Seed is used when there isn't enough corruption to max it out, it increases the total amount of room for corruption in the Soul Gem, meaning the girl can use more magic before being in danger of turning into a witch.
Also, Homura's power appears to only affect her, not the universe. That is, she is sent backwards in time, not that the universe is resetting and she is the only one who knows. The Norns would almost assuredly be able to determine what is going on with regards to Homura, but this would be rather outside of Raven's area of influence, if I am recalling correctly.
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Stand between the Silver Crystal and the Golden Sea.
"Youngsters these days just have no appreciation for the magnificence of the legendary cucumber." --Krityan Elder, Tales of Vesperia.
Also, Homura's power appears to only affect her, not the universe. That is, she is sent backwards in time, not that the universe is resetting and she is the only one who knows. The Norns would almost assuredly be able to determine what is going on with regards to Homura, but this would be rather outside of Raven's area of influence, if I am recalling correctly.
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Stand between the Silver Crystal and the Golden Sea.
"Youngsters these days just have no appreciation for the magnificence of the legendary cucumber." --Krityan Elder, Tales of Vesperia.