Breaking Points are the Sleeper equivalent of Acts of Hubris, as their minds try to understand the Supernal against the forces of Quiescence and Dissonance
Instead of Wisdom, Sleepers, Sleepwalkers, and Proximi use an Advantage called Integrity which represents the health of their souls and senses of self. Instead of Acts of Hubris, Sleepers risk breaking points when they suffer psychological stress.
Witnessing magic is always a breaking point, as is killing another human being; but the Storyteller and players should work together to define a few situations that would constitute a breaking point for each character.
Characters using Integrity roll Resolve + Composure when they reach a breaking point, with modifiers for high or low Integrity (8–10 gives +2 dice, 7–6 is +1, 3–2 is –1 and 1 is –2) or situational modifiers decided by the Storyteller.
Whether the character succeeds or fails, reaching a breaking point applies a Condition such as Guilty, Shaken, or Spooked.
Failing the roll means the character loses a dot of Integrity.
Dramatically failing grants a Beat and changes the Condition to a worse one like Broken, Fugue, or Madness.
Only exceptional success escapes a negative Condition; the character regains a point of Willpower and takes a Beat instead.
Characters at Integrity 1 continue to suffer breaking points but cannot go to Integrity 0. Integrity may be raised after a protracted period of rest (and, potentially, counselling) for 3 Experiences per dot.