Blizzard Entertainment have announced they have disabled Mei as a playable character from now until November 15. This is due to a major glitch discovered by players. Mei’s Ice Wall ability has created an issue where players are able to reach locations that the developers did not attend to be accessible.
The company posted the following:
We are temporarily disabling Mei to address a bug with her Ice Wall ability that allowed heroes to reach unintended locations when used with their abilities. We are working to address these issues as quickly as possible and aim to bring Mei back in our next upcoming patch which is set for November 15. Thank you for your understanding and patience.
As a reminder, our Blizzard In-Game Code of Conduct 21 specifies that exploiting in-game bugs to gain an unfair advantage is considered cheating and should be reported using our reporting tool in-game 21. Thank you for helping us keep a fun and fair experience for all players.