The game was not playable because it just showed a black screen in the game frame after signing up.
Viewing post in Shadow Alchemy Monsters Academy comments
As you may have noticed, the application is in the development phase. That's why we have disabled login with real email accounts and provided the option to signup with a test account that is not linked to an email and uses dummy data.
Unfortunately, we did not anticipate that there would be a challenge accessing the application through embedded content.
Thanks for feedback we will try to make it playable from embeded here on Itch.io
Thank you for bringing attention to this unexpected bug. Upon further investigation, we discovered that it is an embedded CSRF protection that prevents access from third-party websites. The challenge arose because embedded content from the web application was included in plain HTML uploaded to Itch.io.