Twitch Plays Pokemon is celebrating its third anniversary of the pocket monsters play through by playing a heavily modified version of Pokemon Yellow en masse.

Believe it or not, it's been three years since Twitch first played Pokemon, establishing a tradition that's stood ever since. To mark this milestone, the channel is playing through a version of Pokemon Yellow — albeit one that's been modified to amp up the chaos.

For the uninitiated, Twitch Plays Pokemon is a channel that allows everyone in its chatroom to influence a run through a particular Pokemon game. Viewers post their desired input in the chat box, and a bot translates these messages into in-game commands.

It's not easy for thousands of viewers to settle on the same strategy, especially when a certain percentage of them are explicitly trying to go against the flow. However, things click eventually; the first Twitch Plays Pokemon event in 2014 managed to clear Pokemon Red in just 16 days.

Plenty of Pokemon titles have been vanquished since then, from classics like Pokemon Crystal, to spin-off titles like Pokemon XD, and even the most recent mainline instalment, Pokemon Sun. The latest challenge is Pokemon Yellow — but not the Pokemon Yellow you might remember from the late 90s.

Rather than Pikachu following the player round, it's an unofficial Pokemon called Chatot, according to a report from Kotaku. This particular pocket monster is kitted out with all kinds of ways to use messages sent in Twitch chat, making things all the more unpredictable.

For instance, the player character might speak to Chatot, only to be given a message plucked from chat as its response. The monster also has a special move called Chatter, which has different effects depending on which emote is submitted in the chat box.

This isn't the only modification that's been made to the game. All non-player character dialog, signage, Pokedex entries, and certain other text has been replaced by messages generated from chat. As you can imagine, this offers up plenty of capacity for offensive content. However, the project's creator has stated that moderators have the ability to censor any messages that aren't entirely appropriate, to ensure that the stream retains a fun, friendly atmosphere.

Twitch Plays Pokemon is one of the most creative channels that's ever appeared on Twitch, and it's great to see the concept still going strong after three years. The stream is now underway, and will continue until Pokemon Yellow has been completed — however long it takes.