So, I really remembered having Mama Mush unlocked as a challenger, except now she doesn't show anywhere on my battlers. I also have been trying to go to the arctic frost to unlock her in the case that I just somehow remembered having a challenger I don't have, however, she never shows up. I have managed to get to the Slush page multiple times without the frozen cookie and she doesn't show up. I know it is a chance for her to show up in this case, not a guarantee, but I've hit the page I'm not sure how many times and nothing.

Thanks in advance for the help! =3

Are you sure you have checked under the Secret tab in the Coliseum on the challenge page? There are kind of a lot of secret challengers now, but she should show up somewhere on that page if you do have her unlocked.

Yep, I've checked all the challenger tabs and nothing. I really remembered seeing her on this page before but not she's not there. And I cant seem to unlock her even if I really didn't have her unlocked before.

Well apparently even if you reach the slush page without the cookie, it's still a random unlock. So it could take you several tries before unlocking.

If it still seems to take you a few tries of doing that without unlocking her and you feel like you may have had her unlocked before, I would recommend filing a ticket so a UA can look into your account logs and see if anything weird happened somehow.

Sounds good. I think I will. I have hit the slush page without the cookie at least 10 times with no luck. Maybe I just have poor luck.