Crystal Cocoon my Beloved

[StarMann]

Being able to cast during crystal cocoon is indeed a bug and unintended. However it is impossible to try and police as the ideal use for an immune is to attempt to use an ability the frame it ends and so you will get even the best players casting during it if they want to use it. Currently the spell is not banned or anything. We just ask people to be mindful about it. It will, hopefully soon, be fixed to work as intended.

For now, the ruling is that you shouldn't but there's no way to stop you without banning the spell, which we aren't doing.

Edit: He can change his mind if he so wishes, however