Simple Bass line help

[Regulan]

Can anyone give me some pointers on how to play this line? A friend has it in her video and I have wanted to learn how to play it for the longest time. It sounds fairly simple, but I'm having trouble figuring it out.

Here is a link to a video with the bass line in it: http://www.youtube.com/watch?v=XzxKww-hGDU
FYI, that is not the video my friend made, lol.

[Deathblade Eric]

C1 G2 Bb2 C2 Bb2 G2 Bb2 C2, C1 G2 Bb2 C2 Bb2 G2 & repeat until your arm drops off

The bit at the end is C1 E2 F2 G2.

If you're having difficulty with this kind of thing, look up the 'Pentatonic Scale' - it will serve you very well indeed (Geezer Butler based an entire career around it ).

Pete.