Although the Burning Legion was infamous in the future, who would have thought that the newly established Legion was actually like a headless fly running around in a mess?
After leaving with Sargeras and finding the Twisting Nether demons released from Mardum, Roy found that these guys, who had just escaped from prison, were happily venting their bloodthirsty desires.
Yes, these guys were fighting among themselves, and the situation of them killing each other was even more violent than in prison.