This spell is a part of the Flashback spell chain and is found in the Flashback rune stone.
Rumination does not forget. This is important to understand about the dark symbol of past magic, Rumination holds everything it has ever touched with the same relentless grip it brings to every wound, every failure, every moment it has decided deserves to be turned over and examined indefinitely. It does not forget. But it does something considerably more useful in certain situations - it makes others forget. Not randomly. Not broadly. Rumination is precise about what it chooses to interfere with, and what it chooses is always the newest things - the skills most recently acquired, the spells most recently learned, the knowledge that represents the target's most recent growth. Rumination has no interest in ancient history. It is interested in the version of the target that existed before they became what they currently are, and it reaches into their mind to retrieve that earlier version by stripping away what came after.
When this spell is cast Rumination pulls the target's mind backward through their own learning history. A 1d10 is rolled - the number indicating how many of the target's most recently acquired skills and spells Rumination unravels, working backward through their development from most recent to less recent, taking only those that nothing else depends on knowing. The target finds that knowledge simply absent, the capabilities they built through effort and experience suddenly inaccessible as if they were learned by someone else and never truly theirs. When the spell ends Rumination releases its grip and the knowledge returns. Everything snapping back into place as the target's mind reasserts what it actually knows. Rumination does not keep what it takes. It simply demonstrates, for the duration, that what the target has built can always be questioned.
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