I kept it very very simple because it's just a tut on a tag, not how to make an effect or how to work your way around Gimp. It's really for people who are experienced with graphics. And Harrinator, I'd rather not for you to post my tut on the site, just put a link there referring back to this site or my devart. D:
I suggest using these sprites, they're very popular (the hgh kb ones). http://sdb.drshnaps.com/sheets/SNK/Other/ Because the Halo sprites are too small to work with, or even see. >____>
Yaff is right, it's not a vector. Vector has the ability to zoom in without losing detail, the ability to se more detail in fact. PNG's are squares when you zoom in. :-#
You didn't do anything to the render.. :s You don't put them in just for something to look at, at least do something with it other than hide it behind a few layers.