WOW!!! this really is just TOO big of a question!!!
there are so many great artists and styles that it's really hard for me to choose only one favorite.
if i had to narrow it down i'd say my all time favorite artist would be Richard Corben.
the art he did for Creepy magazine and his Den series were just incredible!!
having him do art for Ninja Turtles as truly a gift!
but i think the collaborated efforts from various artists was some of my favorite early Mirage art.