I want giant angry cave troll!!!! 
lol, I like the fish. You should have him menacingly lent over a small fish (reference Finding Nemo) but also have a giant silhouette of an even bigger fish in the background.
www.stevenegan-cgi.com
"Your weapons are no match for ours! People of Mars, surrender!"
"Um, this isn't Mars. This is Earth."
"Earth? Earth-with-nuclear-weapons Earth?"
"Yes."
[long pause] "Friend!!"