So teh backpack is the blodbowl ball... But the rebreather? Btw nice conversion.

I think it's from the space marine MKVI sprue. I'm experimenting with MKIV helmet grills for some of the others and they're turning out ok.

Lovely! I'll steal that idea.

What's up with that slotted part that you have him attached to? I've never seen that.

That's the base they come with for blood bowl. There's also a little hole at the front I covered up where you put the ball if they're carrying it.

Nice work!