User blog comment:GTA Myth Hunter01/Call of Duty Advanced Warfare Exo Zombies Analyzis/@comment-1916935-20150124033013/@comment-24001421-20150124061108

yep, thats pretty much likely what theyre doing. as for the copyright part though, i dont think that the hounds and other types of enemies are copyrighted by 3arc. maybe by activision, but likely not by 3arc themselves; its more likely that they just didnt wanna use the same types of zombies 3arc did. i mean, the regular zombies look practically the same, so...

plus, sledgehammer used things by other companies in their game already, like the pick 10 (now pick 13) and many weapons from codg, so thats more proof that its likely that its copyright issues.