Valve’s $18 million Dota 2 tournament The International 5 delayed by DDoS attack

The world’s largest eSports tournament, The International 5 kicked off on Monday, bringing the world’s best Dota 2 players together in Seattle’s Key Arena. With $18 million in prizes on the line, every single match is a high stakes match, so when a match is delayed, it’s a big deal.

And when a match is delayed for over three hours due to a distributed denial-of-service (DDoS) attack, it’s an even bigger deal, but that is exactly what happened yesterday. The first game of three between Evil Geniuses and compLexity Gaming was hit by sudden lag and was eventually paused.

Valve’s on-stage commentators confirmed to the audience that the pause was in fact due to a DDoS attack, VentureBeat reports. The actual stream of the event wasn’t affected, so the hosts filled in by analyzing the gameplay from the teams so far and showing other coverage. The game was back on at roughly 1:20 p.m. PDT, but the three-hour delay reveals a major crimp in Valve’s planning for the tournament.

Unlike older PC games, most modern games don’t include LAN support for networked play without connecting to the Internet. Dota 2 is no different, so even for these large tournaments, players are connected to servers on the Internet, the same as when gamers play Dota 2 anywhere else in the world. This is what allowed the DDoS to affect the tournament in the way it did.

Valve is almost certainly hard at work putting methods in place to keep this from happening again during The International 5, but this isn’t an easy thing to do. While it’s unlikely we’ll see the introduction of a LAN mode in Dota 2 simply to allow for DDoS-free tournaments, we can always hope.

The International 5 will run through this Saturday, and there are many more matches to go before one team is crowned the winner. To see what the tournament is all about, take a look at our guide on how to watch the event.