A second Fly Agaric post, Amanita muscaria is the scientific name for the mushroom.
Although classified as poisonous it hasn’t stopped slugs or snails eating part of the cap of the one on the right. You can just see the edge of eaten section slightly right of centre of the top of the cap.
At the same time, the reason it is called Fly Agaric in English is because in the past the mushroom was powdered into milk to kill flies in parts of Europe. Bug Agaric is an old alternative name for the mushroom for the same reason.