Honor is a progression system in League of Legends that incentivizes friendly behavior and rewards players who positively influence the game.
Rewards such as keys, fragments, capsules, emotes, and even exclusive skins, like Medieval Twitch and Grey Warwick, are up for grabs and can be obtained by increasing your honor level.
At the end of each match, every player in the lobby will have the option to commend one other teammate in one of three categories:
There’s Stayed Cool for teammates that were “tilt-proof and chill,” Great Shotcalling, which is reserved for teammates with good leadership skills and strategy, and GG <3, targeted at friendly teammates.
To increase your honor in League, all you can do is play the game with a positive attitude and hope for the best. The progression system isn’t explicitly tied to a specific number of honors received, meaning there’s an element of luck involved.
As long as you’re friendly and polite to your teammates and you try your absolute best to win, you should eventually reach the fifth and final Honor level.[source dotesports.com]