The tardigrade resembles a microscopic manatee, and it has one thing on its to-do list: Be unkillable. These micro-animals live in arctic ice, volcanoes, radiation that would turn the Hulk to dust, and can even survive in the vacuum of space. No food? No problem! Tardigrades can shut down their metabolism for up to a decade. Every badass thing you've ever done or ever will do is dwarfed by this little Gummi Bear.