This heavily forested scene would not look at all out of place in Oblivion or Skyrim. In the foreground a Guardian advances on the abandoned tower.

Another shot that appears to be in-engine, showing off some neat ray of light effects.

Marty O'Donnell.

"We're creating something completely new, and that's a scary place, but if it's not scary, then it isn't going to be good."

-- Martin O'Donnell

This scene looks like it belongs to Earth's moon, perhaps overlooking the Hellmouth location pictured in other concept art images.

The color scheme makes this scene seem reminiscent of Covenant environments from Halo, but the structural elements in the distance seem human in origin, while those closer to the camera have that vaguely organic look Bungie has assigned to alien technology, most notably the Pfhor and the Covenant.

No action here, but our Guardian buddies sure do look good walking up some stairs.

The group of Guardians continue to advance towards the portal-like object.

As the players pass, the low pod-like object on the ground to the left glows with a golden sheen, perhaps indicating that it is a territorial marker, or perhaps something analogous to a Halo weapon drop pod.

Looking over the barrel of a futuristic-looking gun-- now it seems that we're looking at in-game footage or something close to it.

The artifact in the distance glowing blue may be some kind of transportation portal used for fast travel while on planets-- sort of like a World Knot from Myth.

The best thing about Bungie is, even though you know you have these crazy ideas, you know that they're going to get funnelled into a game that's fun.