Felix was a reformed ex-Stasi. He didn't follow his past anymore. He barely tried to let it control him, but at the casino, he let it slip. He didn't condone himself for this, and frankly, he was barely able to take his mind off it.
Just after Adler informed Marshall and the team about how Gusev fled the lab he tracked down, Adler planning to have a few members meet with an old friend of his, Sims, Sev had spoken to Felix.
"You were impressive today. Finally, the great Felix Neumann in action!" Sev seemed almost proud, joining Felix by the burning barrel to warm her hands. All he replied with was a simple, "Yes."
Sev was taken aback, "What's on your mind?" She asked in a softer tone. Felix was silent, contemplating.
"I need to make a confession." Felix finally said after what felt like an eternity in his mind.
Sev chuckled, smiling. "I'm the furthest thing from a priest, Felix, but speak your mind." She took a seat on the guard rails, hands by her sides.
"I am deeply ashamed of my actions at the casino." Felix admitted, pacing a few steps.
"You take this "non-violence" thing seriously." Sev pointed out, holding her leg that sat on the rail.
"Quite." Felix turned to face Sev. "But then I saw Luttazzi thugs beating a defenseless man. Mercilessly. A senseless act of power." He had a hint of disgust in his tone, nearly sneering out his words.
Sev chimed in after a second, "No one is innocent in that city."
Felix began again, "Afterward, when I encountered the guard outside the vault, I lost control. My eyes transformed into the avatar of everything I now reject."
He took a moment to speak again. "So I punished him."
"Good. Probably less than what he deserved." Sev said with a quiet huff.
Felix took a step closer to her, "If I lose myself to this endeavor, I am no better than the enemy we seek to stop, ja?"