I have heard of Alice. Alice is a boring machine that chews up rock. Kind of like a big metal tapeworm. This type is called an "edgebander."

The thermal boring machines are entirely different. If you read that first article, you see they managed to make a 2" diameter hole and were hoping to work up to four inches. I have some reports on that project, I believe. That was in the 1970s. Now it is 52 years later and this startup company is the latest thing: https://www.industrytap.com/amazing-no-contact-thermal-boring-machine-can-cut-through-un-drillable-rocks/61355 This advanced version can cut a hole up to 60" and has managed to make a hole 20 feet long. Still would take quite a long time to drain Lake Mead.

The original idea has now turned into an urban myth about nuclear powered borers, or maybe plasma cutters adapted to rock, that melt rock like butter and have allowed evil reptilian overlords, or maybe satanist pedovores, to dig luxurious underground hideouts ten kilometers down. The inconvenience of locating these structures under sea beds and massive dams and volcanos is more than made up by the concealment qualities of being under millions of tons of rock, in a balmy ambiance of 200 degrees Celsius. Too bad nothing more has been said about these wonderful machines since 1995, when a certain person gave an interview describing these tunnels, but his story has been picked up over and over so it is now a matter of faith in some quarters.