During the intervening years, Alabama was the site of some of the most defining events of the civil rights era. These events transformed the state and profoundly changed America. Black protest started long before the civil rights movement emerged and continued long after it stopped receiving front-page headlines.
Also, you can play versus(and survival, if you get the GOTY edition) offline by selecting join friends, the pressing X to start your own lobby, it tricks the game into letting you play the modes. Why there wasn't just an offline option on the main menu is beyond me.
You won't lose Champion Mastery points by losing and/or sucking. Furthermore, points won't decay if you haven't played a character in a while. That said, Riot doesn't want to make this a complete cakewalk. You can't just max out Champion Mastery by playing bot games.