The Fairest Badge
From City of Heroes: Rebirth - Wiki
Description
Working with the government and your mirror self from another dimension, you stopped your evil doppleganger's plans to cause chaos and destruction throughout Paragon.
How to Get
Complete the Defeat your Evil Double mission given by Field Agent Keith Nance.
Notes
The The Fairest badge is awarded to characters of the hero and vigilante alignments. The same badge on villains and rogues is called Turf Protector.