Rika who was being attacked by Lyner was thinking, she knew what the monster of Berdonia was saying was right. She knew that the people on the top of the Empire's food chain, weren't actual good people. She knew that attacking Berdonia wasn't right, but she must still do it for the people of the Granado Empire. Even though she knew all these, she couldn't stop since the Granado Empire has done too much, that they have passed the point of no return.
The reason she was able to figure this all out was because when Rika was released from prison to kill Lyner, the first thing she did was to gather information so that she could understand what had happened. Also to figure out what kind of person her opponent was.
S&W is Smith and Wesson