Legate hurts your soul.

The Legate had speed and power too, but his blows seemed to cause her far more pain than simple impact warranted.

Suddenly they stopped, Rampage’s face frozen in a mask of agony. “How…” she gasped.

The Legate stood smugly. “A simple disruption of your body’s biorhythms and connection to your soul. The imbalances build and resonate until–” He reached out and poked the stricken mare’s chest. Suddenly her whole body spasmed and seemed to compress all at once. Her mouth opened in a silent scream, and blood erupted from her maw. She finally slumped but didn’t quite fall, looking as if a massive hand had squeezed her. “That.”

Fallout Equestria Project Horizons Chapter 65: https://www.fimfiction.net/story/208056/66/fallout-equestria-project-horizons/chapter-65-knowledge