The deer flower fungus (scientific name Gyromitra esculenta) is fatal enough when eaten raw. It is also called “brain mushroom” due to its convoluted surface.
In Spain, Sweden and other places, some people still cooked it and ate it. Deer flower fungus is generally considered to be less toxic. Unlike many other poisonous mushrooms, deer flower bacteria usually cause neurological symptoms, including coma and gastrointestinal upset.