UPDATE 9/4/19: The Spikels Max Pose has been found While searching on the wiki I found some merchandise with some of the 2014 maxes on it.
They actually have action poses just like every mixel from series 1-3 hadAlso on the canada website for CN the Fang Gang Max appeared with an action pose as well
Some Maxes that don't have artwork or haven't been seen
Electroids MaxFlexers Max
who knows, maybe we'll find more lost media stuff