Oh really? http://eatcreatures.com/item/cartoon-rpg-characters-4/ http://eatcreatures.com/item/rpg-weapons/ and the list goes on and on.
I suppose any artist uses references sometimes. I see no problem with it.
That's not a reference, but a pixel perfect copy :D If you are doing that, may as well include all their assets.
a casa caiu xD kkk