Halo 3

Use this video, I used it and it saved me a whole lot of time versus me finding it myself:

http://vimeo.com/3458939

Thanks to Adam Pisani for this video.

For this skull just go outside to where you can see these giant metal arms in the middle of the map. Go to both of them(the arms) to check which arm has the skull once you find it just go back to human form and snag it.

For those of us who aren't fully versed on all the Halo lore, etc... I'll say this plainly so that you don't have to go hunting for the answer like I did.

In order to get all 6 of the Vidmaster Challenge: Brainpan skulls, *all you need* is Halo: ODST. I'm saying this so that you know you don't have to buy the Mythic pack for Halo 3. ODST has those maps on the second disc, and those maps do contain the 3 skulls from Halo 3.

So in other words, if you have ODST, you can get all 6 skulls, including this one, on the multiplayer disc (very, very easily, and get yourself a quick 175 GS in under an hour), or you can use Halo with the two Mythic packs. All of the skulls are available in both places.

I highly recommend the videos that ryankelty posted in the Vidmaster: Brainpan guide. They are excellent, and I want to give him credit for finding them (and to the players who posted them), although I'm going to put them up here for easy reference.

This skull, Assembly, is in the first video. The second is for your convenience if you're looking for all six.

Cheers!

Use this youtube video, to help with the location:

It is sitting on top of one of the branches off of the middle structure, nearest the blue base.