Triple integral bounds question

Setting the bounds for triple integrals has me stumped!!!! Once I set the limits, it just becomes like doing a double but...without the proper bounds I am sunk.

I am to find the volume of the pyramid with base in the plane z = - 6 and sides formed by the three planes y = 0, y - x = 4 and 2x + y + z = 4

On this one I am also not sure what the function is!!!!!! Is it 2x + y + z - 4?

I think my outer most integral should be dz and go from -6 to 0 but for y I can come up with only x + 4 to 0 and then x from y - 4 to 0 and I know I can't have a variable like that in the second limits.

Thanks for taking the time to look at this. Frostking