This spell is a part of the Psy Dagger spell chain and is found in the Psy Dagger rune stone.
The mentimancer understands something that most people learn only accidentally. They understand that the mind performs closer to its actual capacity when it believes in that capacity. Remove the doubt. Remove the self-imposed ceiling. Give the mind permission to be as sharp as it actually is, and it will surprise you.
Mental Muscle is Dream applied to intellect directly - the mentimancer reaching through Dream and simply telling the recipient's mind that it is stronger than it has been acting. Not an illusion. Not a temporary fiction. A genuine enhancement, Dream's conviction settling into the recipient's thinking and sharpening it, Intellect traits increasing by 1 for the duration as the mind expands to fill the space Dream has opened for it. The effect lasts hours, long enough to matter well beyond whatever immediate challenge prompted the casting. The mind, given permission, is capable of more than most people allow it to be. Dream gives that permission freely.
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