This comes from the Viking context image for a MGS image depicting "Ridge margin of lobe to west of Arsia Mons" (Arsia Mons itself sporting a stunning number of face-like forms, the vast majority in seeming aligned sets of profiles).

There are many strange things in this image if you look closely, including one possible very large Cydonia-like face along with many other possible faces. Of course, I could be in error about them, but even if they look less than face-like, they seem to contain recognizable traces, and there's always room for a serious discussion about possible methods of contructing Martian Faces, because for all we yet know, some of the finest examples of Faces on Mars have looked surprisingly much more face-like that what we could hope for on what we know can be a tumultously changing planet.

There's a great likelihood of abbrevating labor by picking face like forms, altering them slightly, then filling in the rough parts with material which would later be easily re-distributed, leaving these scarred, vague face forms that still contain only the barest minumum of recognizable parts.

One other possible place for error lies in the identification of pyramidal artifacts, such as the one speculatively colored in in green. It's easy for the eye to be tricked sometimes, and pyramids that can be confirmed by their shadows are greatly preferred. Still, we don't quite know the origin of the many possible tricks on the eye... should even the false pyramids exist in such numbers without some artificiality and deliberacy? With the great number of what appear to be highly advanced artistic and visual techniques that may have been employed in extraterrestrial art, we cannot rule out a number of two dimensional forms that readily appear to us three dimensional, because that is precisely what they may have been designed to do, as well as communicating more of the relevant geometrical and mathematical messages we have already become accustomed to.