Mei's Ice Wall ability is potentially one of the strongest abilities in the game, but there are some inconsistencies about the true power of the it. There are myths that seem to float around, and there are facts that are blown over. Here are the two most common.
Let me start with the biggest one first.
FICTION: MEI'S ICE WALL CHARGES HER ULTIMATE WHEN ATTACKED.
This is a very common misconception about her wall. Too many believe that attacking the wall can earn Mei 8-10 ultimate percentage. I personally went in and tested it with a Bastion to shoot my wall down. No changes were made (If I had the ability to record, I would have recorded it and posted it. I will be linking sources at the end).
FACT: MEI'S ICE WALL GIVES MEI 'ON FIRE' POINTS.
While not administering Mei ultimate charge, the wall does add to her 'on fire' meter to show how well a player is doing in-game. It is the same as Rein, DVA, Zarya, and Winston shields. You do not see their ultimates charging faster by blocking.
Remember to keep in mind where you get your information from. I will give online sources below.
http://us.battle.net/forums/en/overwatch/topic/20748896467
https://www.youtube.com/watch?v=OPeg8R9mFLk - this video is a bit old (You can see that her Cryofreeze doesn't charge her ultimate), but you can notice early in the video where a bastion demonstrates the health of it, and she does not gain ultimate charge.
https://www.reddit.com/r/Overwatch/comments/52e5ea/does_shooting_meis_wall_give_her_ult_charge/
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