This is a continually updated post.
(Before you comment saying "Nothing new", I've read all the ToS Riot has released so far, so I know already what the previous version were. The Dec 6 ToS mostly a definition update.)
If you want to read the entire ToS for yourself, because you may have just pressed accept as soon as the patch finished and not read a damn thing you can do so [here](https://na.leagueoflegends.com/en/legal/termsofuse). (NA)
So what exactly has changed? Well, they made first off now I can't directly copy-paste the wording from the client to here so thanks Riot.
The short summary is:
If you post League of Legends material, Riot Games owns that material.
You do not own anything in League of Legends.
You can be banned for any reason or punished for any of these reasons:
Cheating, boosting, modifying any content, harassing, stalking, posting identifying information, social engineering, summoner names, leaving games, or convincing anybody else to do any of the aforementioned.
(Punishments are not limited to what is listed, Riot Games will punish you for any Reason, without a need for notification.)
Boards Specific: "Your Content" if uploaded, belongs to Riot Games and you are due nothing.
Boards Specific: You are responsible for content on the boards. Riot claims no responsibility even for links they themselves post.
Riot is watching you, and will use your information however they please.
If someone DMCA strikes you that is not Riot, contact Riot.
If you want to dispute a DMCA with Riot, send us your fucking info bitch and here's our address.
Riot Games is not responsible for anything "As Is" (Player experience, content, not even the game, etc...)
If you sue Riot Games, you agree to indemnification (You pay for Riot's legal expenses).
You cannot sue Riot Games and another affiliate of Riot Games at the same time.
You agree to no class action law suit against Riot Games (Large groups of people against Riot Games)
You agree to arbitration. (A "private third-party" that Riot picks (**JAMSADR**) for dispute resolution.)
The arbitrator decides what you get. (Nothing.)
If you're in California, prepare to get FUCKED trying to arbitrate or sue.
Everything about arbitration is done in secret.
Things that aren't legally enforceable (like owning user created content) can be dropped.
Riot Games can breech the agreement.
You also agree to future stuff Riot Games hasn't thought of or listed.
That was a read on it's own if you made it down here.
Breaking down some key things:
Hey, they're talking about the Tribunal, let's go see if it's up!
Yeah no, you came back and you're just as disappointed as me.
Here's an interesting link concerning User Created content
Language is very important, also it's non-binding.
Refunds, and why you probably won't get one.
Riot owns everything, can do whatever they want, and they're not liable for anything, even their own links or boards posts.
The line that hurts the most though.
TLDR; Riot can do whatever they want, you get to play the game.
I've come to the conspiracy theory that the definition update is part of the backlash from the API changes. I have no proof, I'm literally doing the (21) = 7+7+7 someone else did earlier. I could imagine the loss of internet traffic to third-parties that relied heavily on the previous iteration of the Riot API.