Arcane Resilience

Arcane Resilience can be simply described as magic willpower. It is a magic user's ability to control and resist the physical and mental effects of powerful magic. The more powerful the magic the caster attempts the harder the body will have to struggle to resist the effect of the magic (this is especially true if the caster has high Arcane Potential.) All individuals have an arcane resilience, including those who do not practice or use magic. Arcane Resilience is not directly affected by Arcane Potential, thus an individual could have an immense Arcane Potential but low Arcane Resilience and vice-versa. Arcane Resilience also affects a individual's use of Dilieiusmency, though as this skill itself is rare few individuals ever experience this link.
Description by Kherson Moria, The Sage:
"Arcane Resilience is arcane strength and will, and is more crucial to a wielder of magic than Arcane Potential. Arcane Resilience is far less understood, even among magic users, than Arcane Potential. For most the former is best described as a form of durability while the latter is a form of potency. These definitions and their usage is reductionist, and therefore are only useful to a limited degree. Arcane Resilience is not only a physical and mental strength but a moral strength, the strength to resist the temptation that magic presents. Magic is power made manifest, and more accessible to most than armies, titles, or wealth. A dark heart can harbor as great Arcane Resilience as can a good heart, but their resilience is much more fragile. Building your strength and resilience on base desires allows emotion to twist one's magic more than magic founded upon a more stable foundation of consideration and serenity."
(For Game Rules see Arcane Resilience)