Pokemon Go fans are turning on the Niantic game because of Ex Raids.
Ex Raids are exclusive invitation-only raids that are only open to select players. They also represent the only way in which fans can capture Legendary Pokemon Mewtwo.
The seemingly random nature of the invitation process has rubbed some fans up the wrong way, including Pokemon Go YouTuber Reversal.
Things have gotten so bad that Reversal told fans that he is taking a break from the game (via Polygon).
"You know what? I'm done with this EX-Raid Pass System," he tweeted. "Way to kill my motivation on this game. Taking a indefinite break from #PokemonGO"
Niantic gave the Ex Raid system a big update in November, supposedly in order to make them accessible to more players.
As part of the changes, players with lots of Raid experience are more likely to be invited.
Likewise, invitations are more likely to be sent out to Trainers with high level gym badges.
Considering the criteria, it's easy to see why some of Pokemon Go's hardcore fans are upset.
Exclusive, for example, recently tweeted that he had been passed up for more than 30 Ex Raids.
The news comes as fans were treated to a surprise Gen 3 switch.
Mirroring their famous rivalry in the Pokemon games and TV show, Gen 3 regional exclusives Seviper and Zangoose have now swapped places.
UK players can now catch Zangoose, while Seviper has migrated to the US, Canada, South America and Africa.
With Niantic yet to make an official announcement, it's unclear how long the switch will last.