Phase detection on Irengar the Pale

We wanted phase markers on Run Detail. Sounds simple — detect when one phase ends and another begins. The signals are noisy.

We ended up with three heuristics: (1) sustained drop in raid DPS for 5+ seconds, (2) a known phase-transition spell ID in the cast log, (3) HP threshold crossings on the boss target.

Combining all three gets us to 92% precision on detected transitions. The remaining 8% are weird edge cases we now handle as exceptions.