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The makers of the (in)famous "BigDog" four-legged robot have released a handful of videos showing off their latest creations. From BigDog's successor to the speedy "WildCat" to the eerie human analogue "Atlas," the robots are as impressive — and creepy — as ever.

Boston Dynamics

First up from Boston Dynamics is the Legged Squad Support System, or LS3, as the latest in the BigDog line is called. The field testing video above shows the high-stepping robo-critter ascending and descending a steep slope while laden with packs, and then trudging through snow back in its native Boston.

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Keeping all those parts working in both desert heat and wet, frozen conditions can't be an easy task, but the LS3, if it is ever deployed, will be expected to function regardless of weather — like the soldiers it serves.

Next is Atlas, the human analogue that walks on two feet and balances just like a person would. Watch it traverse some rubble here:

Not the most elegant gait, but it gets the job done. And its response to being struck by a 20-pound ball is almost scarily humanoid.

Lastly there is a new robot in the Boston Dynamics stable: the Wildcat. The video can speak for itself:

It appears to be a descendant of the Cheetah robot, which in controlled circumstances can hit 29 miles per hour, a record for legged robots. While the WildCat's loud gas engine makes it rather unsuitable for stealth missions, it could fill other roles on the battlefield and in civilian life.

As usual, the creepiness of Boston Dynamics' robots is matched (caused, in fact) only by the impressive engineering enabling such natural motion. Funding for these projects is provided by the Defense Department's research arm, DARPA.

Devin Coldewey is a contributing writer for NBC News Digital. His personal website is coldewey.cc.