Judging by the image Vestmann poster, RDNA use a strange definition of "oblong". To my mind an oblong is an elongated square.

I took my own advice and made a couple of morphs using magnets. Does the image above represent the sort of shape you want? If so I'll package the morphs and post them. There are two morphs, one to make the head square and one to make it longer, so you can vary these factors independently.