Chronobreak Tool Introduced to League of Legends

by Matt Best

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(Photo: lolesports)


If you've ever watched a professional League of Legends game, when something goes wrong, "Remake!" is scattered throughout Twitch chat.

During the marquee match up of the split between Cloud9 and FlyQuest, fans almost got their wish.


Instead, fans were treated to the introduction of Riot's "Terministic Disaster Recovery Tool", also known as "Chronobreak". 

In case you missed it, Johnny "Altec" Ru's ultimate as Miss Fortune was blocked by a minion. Altec knew something was up and requested a pause at 10:47. Take a peek below at the six second mark and you'll see MF's ultimate get blocked.

This completely altered the team fight in the bot lane. Andy "Smoothie" Ta did still take all the damage but the visual bug certainly confused the likes of Altec and spectators.

So what is this Chronobreak tool? It allows the game to be rewound to a certain point in the match without having to remake the game and go through picks and bans again. One of Riot's engineers, RiotBrentmeister, took to a Reddit thread and helped explain the ins and outs of the tool. "In order for this tool to work we needed to make sure that we capture 100% of inputs for the game and when we play them back the server executes in the EXACT same way every time. Replays are client-side which is a bit different because the client just visualizes what it gets from the replay file. With DDR we have to get 100% of the server state recorded just right. To do this we rewrote the in-game clocks, random number generators and more to do this. The biggest factor that helped this was the tireless efforts of all teams at Riot to make the code more sustainable and predictable." Basically, think of a time machine. Riot has a time machine. 

You might be wondering by now, how did they land on a certain rewind point? Raven "Riotraves" Keene, Head Referee said, "I was trying to find a time close enough where people were not engaged. A few seconds earlier than the time chosen had the laners engaged while a few seconds later had them much closer with less to no opportunity for possible counterplay out of a pause," he explained. "The point we chose had the lane at an almost reset position. We want to place them in the fairest point that gives them the opportunity to still respond outside of the pause, but we dont want to go so far as to lose significant elements of the game state.

Officially titled the "Terministic Disaster Recovery Tool", some have started calling it "DDR" or "Chronobreak". Caster David "Phreak" Turley spoke about what they have to call it and left with some closing thoughts. "We had a meeting about this before week 1 of the LCS. No matter who it was, we were all informed, "Please call it the full name at the beginning." I have no doubts we'll all start to casualize (?) it in the near future."

"Hopefully, we don't have to use it again for a long time."

By Matt Best

Matt Best is the Lead On Air Host and Producer for WWG. He has spent his professional career submerged in both the traditional sports world as well as esports. As one of the only Canadians at WWG, if you want to tilt Matt, just bring up awful Canadian stereotypes.