I am trying to make a series of battles between Gojira and the Mojaves finest fighters, but the problem arises that Gojira is very large and has a lot of trouble maneuvering over uneven or obstacle-strewn areas, and so tends to get hung up on stuff while the enemy shoots at him (in the case of my VS NCR test), so I am looking to you all for assistance, what area is relatively flat and open, and still large enough for Gojira to move around in.

How about the http://fallout.wikia.com/wiki/El_Dorado_dry_lake

Well, the terrain is reasonably flat and open, but I am worried about the dust storms and ant spawns.

I think the area around the Ivanpah race track would work as well if my memory is correct. Though I think Lord Vukodlak's idea would work better then mine.

Both of those areas have ant spawns and dust storms.

Thats true, but I'm looking at the map of New Vegas and there isn't much large open areas around. Though there is a lot open space near http://fallout.wikia.com/wiki/Nellis_Air_Force_Base. (if you look at the overview picture and to the right of the base where the phone towers or whatever they're called.)

Nellis! Yes! I can easily disable the patrol robots and use their large amounts of open space!

Then kill the ants before hand they don't respawn that quickly, isn't there a console command to basically kill everything in a cell area?

Well the sandstorms are bad enough for recording, and ant spawns will confuse the already derp-tastic AI of Gamebryo

Nellis is decent, what about Searchlight Airport?

Too green. :spotted owl:

Maybe green is a goodthing? Gojira could have been an irradiated abomination?

what about that huge endless terrain south of searchlight? not exactly "in" the map boundaries but it is still big

:0

You can find some pretty flat and empty areas near that place where the Unique Gauss Rifle/ Alien Blaster is.

You could go beyond the game borders. The area beyond the Canyon Wreckage is pretty flat. Doesn't have much in the way of scenery though.

well all the terrain idea's have been said but enemies for him should be Giant robo scorpion(2-3) or legendary deathclaw (2-3)