Toxic fungi are types of mushrooms that produce harmful substances called mycotoxins. These toxins can cause serious health issues in humans and animals if ingested. Some well-known toxic fungi include Amanita phalloides, commonly known as the death cap, which can lead to liver failure, and Cortinarius orellanus, known for causing kidney damage. Identifying toxic fungi can be challenging, as many poisonous species resemble edible ones. It is essential to be cautious when foraging for mushrooms and to rely on expert identification. Consuming even a small amount of toxic fungi can result in severe illness or death.