5 0 0You can get this on the first island with a triceratops. But simply releasing the dinosaur will not work.You need to get it Mad (with a slash symbol on top of it) which will cause it to break out and trample visitors.What i did i place 5 triceratops on a small enclosure next to an area where visitors commonly pass thru. As the comfort level goes down they will attempt to break out.Once it does get out. follow it with the rangers close by and take a picture as it attacks the visitors. You will get the achievement if done correctly.