Death cap
Contains amatoxins that can cause life-threatening liver damage.
Cortinarius rubellus
Русское название: Паутинник красивейший
Contains orellanine, a toxin linked to severe kidney injury. Symptoms can be substantially delayed after eating the fungus. Brown forest mushrooms can be deceptively similar, so photographs are not reliable identification tools.

Never decide to eat a wild mushroom from a photograph or online description. A mistake can be fatal. For mushroom ingestion or suspected poisoning, contact emergency medical services or a poison centre immediately, even if symptoms have not appeared.
Irish Poisons Centre mushroom safety ↗Europe, especially northern and upland forests
Coniferous woodland and acidic soils
Images and brief descriptions are for learning, not for reliably identifying a specimen. Take particular care with poisonous plants and mushrooms.
Identification is never guaranteed by a photo. Scientific names are used to reduce confusion between local names.