I have only 1 problem with TFT

And it's not about the RGN system but more about the class vs pve monster. Playing the sorcerers class isn't fun against dragon, this boss seem to be immune to magic dmg and result into an always death for sorcerers which lead to drop no item. Since sorcerer are suppose to be a late game class, why they are so weak against him? I understand that the dragon should be an hard to kill objectove but this leave no sense since it's too much hard for that class. Fun note assasin can 3 crit dragon and do that without losing a member if they're build really good. Plz make drake able to take half of the magic dmg done.