I believe you're talking about the signature--the image at the bottom of Ashley's posts, right? Yeah, that's his signature.
I'm not sure if non-administrative users of the forums can link images in their sigs, but you can place text there at any rate. Go to your profile and scroll down to the "signature" field. You can write stuff there.
EDIT: It looks like the game cards are HTML embed code. You can paste that stuff in there too.