Animal doesn't have much substance as a horror movie. It's your typical "teenagers lost in the woods and are getting picked off one by one" story, except instead of a machete wielding maniac chasing them it's an Alien-Predator-hybrid animal that has a taste for human meat. For what it is, it's a fun watch - it's exactly what you'd expect from a B-movie called "Animal".
I can't score it any higher because it gets zero points for originality and I can't score it lower because it doesn't try to be anything more than a schlocky monster movie. It's surprisingly cohesive writing-wise, and is definitely more watchable than half the F13 entries. Elizabeth Gillies' ear-piercing screams are annoying yet hilarious and add some extra zest once her friends become fodder to this unstoppable beast.
Overall Animal achieves exactly what it sets out to, but its sights weren't aimed high in the first place. It's a clear homage to old-fashioned monster movies with lots of campiness, cheesy special effects, blood and guts aplenty, and a handful of scares that catch you off-guard. All you can ever want in a B-movie romp-fest.