From NexusWiki

The Deer is found in many locations, including Kugnae, Buya, Nagnang, the Wilderness, and just about anywhere that you would find Squirrels.
Killing a Deer gains you 50 Experience and occasionaly an Antler which are very tasty, it is the Male form of a Doe, which are identical to Deer except for the fact that they don't have Antlers.