Featured there is Amanita Muscaria, which isn't really that poisonous. White Amanitas are lethal, never touch those, but with Muscaria you could have some fun.

Some even theorise that the reason Santa is red and white comes from Amanitas, basically a siberian shaman got fucked up on shrooms and climbed down the middle pole of the tent to give everyone else shrooms as well. Which is why Santa comes from the chimney and gives colorful presents. :) (Or so some people have theorised, I'm not asserting it as fact lol.)

edit and also reindeer love chomping on amanitas, and amanitas are associated with feelings of "flying". and the way these people would get high is that the shaman would eat a lot of shrooms, then after he got high he'd piss in a bowl and that piss would get people really high.)

I'm also curious as to what the symbiotic relationship with the genus Mustelidae is

"If you strike me down, I shall become more powerful than you can possibly imagine."

• mushrooms

Break mycelium in half, now is just two mycelium. Mycelium win every time.

Burning them seems to kill them. As does fungicide.

And the ones that mother gives you don't do anything at all

(╯°□°）╯︵ ┻━┻)

They can save your current progress without pausing. Isn't that easy to understand?

A web of mycelium that permeates the ground and constantly regenerates itself, occasionally producing visible fruiting bodies.
It's "immortal" only in the sense that an organism with distinct genetics doesn't die of old age, but fungi aren't really individual organisms like we are.