Kurzgesagt - In a Nutshell (2013) : 12x16

We’ve found a new planet, home to octillions of the most extreme beings living in the most absurd and deadly hellscape. In absolute darkness, crushed by the weight of mountains, starved of oxygen, cooked alive, bathed in acid, salt or radiation. And yet, they live for thousands, perhaps millions of years! It turns out, this planet is not in space – it is inside the crust of Earth! This is the deep biosphere and we basically learned that it exists yesterday. Its volume is at least twice as large as all the Earth’s oceans, home to more microbes than the rest of the entire planet.Their total biomass is more than 20 times greater than all humans, livestock, and animal wildlife. Let’s descend into this mad, deadly world where none of the rules we thought are mandatory for life apply.