I can’t sit here and guarantee you a robot won’t take your job one day—capitalism kind of has a thing for automation. What I can tell you is that in the near future, robots will be doing jobs that no one wants to do. For instance, risking your life doing rescue operations after mining disasters.

Which is why for its next robotics competition, Darpa is going underground, with the Darpa Subterranean Challenge. If you don’t remember, that’s the same far-out federal research agency that put on the Grand Challenge (which helped kick off the self-driving car revolution), and the Robotics Challenge (which helped get humanoids walking among us). And now it’s calling on researchers to autonomously explore the innards of Earth.

At the TechCrunch Sessions: Robotics conference at UC Berkeley on Friday, the agency gave some clues to a crowd of potential participants about the trials and terrors their robots may face when the challenge kicks off next year.

The challenge will consist of three unique environments. In the first circuit, robots will make their way through tunnels, followed six months later by an underground urban environment, followed six months later by caves. A year after that, teams will navigate a course that includes elements of all three. Although Darpa defines “navigate” loosely: Teams can either tackle the courses physically, or design a simulated spelunker.

Darpa isn’t giving the teams specific tasks, yet—in the Robotics Challenge, for example, robots had to negotiate an environment made for humans, turning valves and climbing stairs and even driving a cart. But it’s clear that they’ll have to deal with some seriously difficult terrain in the Subterranean Challenge, and do it autonomously. After all, connectivity is kinda spotty down there.

“If I'm going through tunnels in urban environments, now I went from having hands-and-knees crawling to turnstiles and escalator frames,” says Timothy Chung, a program manager at Darpa. “How do I span all of the challenges of all those types of environments?”

By getting very creative, is how. A robot may have to climb some stairs, then squeeze through a narrow space in a cave, then tackle mud or even a waterfall. Which means there’s no one form factor that will clearly reign supreme.

Take what happened in the Darpa Robotics Challenge. Robots had to do human tasks, so naturally, teams deployed the humanoid form factor. But a traditional humanoid wasn’t the way to go for everyone. Carnegie Mellon, for instance, deployed a vaguely humanoid machine called Chimp that rolled on its limbs instead of walking. That gave it extra stability. And RoboSimian only looked like a human if you were under the influence of one or more psychedelics.

So maybe the right robots for this new challenge won't be what you’d expect. A quadcopter might do well in the open environment of a human-made structure, but it would smack into the wall of a tight cave pretty quick. A tracked vehicle might do well in tunnels, but get stuck in tight spaces. And I’m betting you’ll see more than one so-called soft robot, which is made of squishy material instead of metal. Some robotic prototypes inflate and elongate, which would be good for squeezing into the tight spaces you’d find in a cave.

And teams won’t be limited to a single, very expensive robot like in the Darpa Robotic Challenge. This will be more of a robotic team effort. So maybe competitors will develop a soft robot for exploration and pair it with a bulkier tracked vehicle that builds a map with lasers. Or, as roboticists have already developed elsewhere, a tracked vehicle with a drone tethered to it.