As this Challenge states you must KILL and LOOT 10 of each animal type. LARGE, SMALL & FLYING during Jan. 27, 2014 - Feb. 28, 2014LARGE
Rat (credit to XboxGamerxXx)Flying
Each types come easy as you going along in the game and should be easy to come by BUT I wanted to state if you started the game before the Challenge went live (Jan. 27, 2014
due to early release in some areas) it might be IMPOSSIBLE to get this challenge if you have gotten the achievements related to this challenge (stated above). I have finished the game and unlocked all single player achievements before the challenge went live and went back to grab the challenge. In doing so nothing unlocked in my 100% game or on a new file when I went back to kill and loot each animal type.
I will keep everybody posted if I figure anything out or hear any news about this challenge. Please if negative message me to help make his solution better so everybody can get this challenge completed. Thanks
EDIT 1 - I uninstalled and reinstalled the game and tried to get the challenge and nothing unlocked. Hopefully a patch will come.
EDIT 2 - Some have stated that Square Enix isn't going to patch it for us who played the game early.