I was just looking back at the leaked images of the Bionicle stand, and it looks a lot like the current promo but with a different mask.
I'm guessing the original, much more tribal mask was a concept version of the Mask of Creation or, as sometimes happens, a mere placeholder while the actual mask was being developed (as in preliminary images of the DC sets for 2015, where Hulk and Ultimate Goblin stand in for Darkseid and Gorilla Grodd respectively).
I really like the Incan-style design of the Mask of Creation (though the Egyptian nemes-style one in the concept art was also cool) and I can't wait for it to come out in a set. When it does, I and the rest of the Gen 1 fandom will no doubt all be working on some Artahka MOCs...
Spoiler (click to read)
For those who didn't follow much of Gen 1, during the story Artahka was the Mask of Creation's original wearer. He ruled a hidden safe haven island named after him and was said to be the world's greatest crafter, that he could build anything out of any material. He was responsible for many things, including making the Kanohi Nuva masks and giving the Toa Nuva their Adaptive Armor and sending them to Karda Nui. He was also one of the oldest beings in the Matoran Universe, if not slightly older than the robot itself.
EDIT: Also, I've merged the topics now to avoid confusion and prompt greater debate bla bla bla Bionicle fanboy alert!
"Nothing goes down 'less I'm involved. No nuggets. No onion rings. No nothin'. A cheeseburger gets sold in the park, I want in! You got fat while we starved on the streets...now it's my turn!" -Harley Morenstein