1. Cryo-Freeze doesn’t use favor-the-player unlike other invulnerability abilities in the game causing Mei to be killable in her Iceblock.
There is already a thread about this problem on the forums which contains more videos.
[Still in the game] Mei can be pulled out of Cry-Freeze by Roadhog's hook
2. The ultimate can get stuck and delayed.
3. Freeze particles can go through ALL walls and is visible to all players (tested with another player).
Freeze particles through walls
4. Wall placement isn’t always correct.
5. Getting teleported around the map when you go up on a Ice-wall.
vlc-record-2018-10-21-22h23m44s-Overwatch 2018.10.12 - 23.44.57.08.mp4-
6. Mei’s ultimate effect gets cancelled by FRIENDLY Reinhardt shatter.
Mei Ultimate Effect Get's Cancelled/delayed By Friendly Shatter/posture Change G... | Gfycat
Source: https://www.reddit.com/r/Overwatch/comments/889gh1/meis_ultimate_effect_gets_cancelled_by_friendly/
Please take a look at some of these bugs. Mei is a fun character to play, but these bugs are somewhat annoying to deal with.
Also, to the players saying that the disappearing ultimate is a bug as well, it isn’t. It’s latency. You can read more about this here: