Dinosaur Island already supports making T. rex pack hunters.

New research recently published in PLOS (“A ‘Terror of Tyrannosaurs’: The First Trackways of Tyrannosaurids and Evidence of Gregariousness and Pathology in Tyrannosauridae” link here) indicates that a ‘cousin’ of the T. rex hunted in packs. Dinosaur Island already supports this behavior by allowing the user to specify that the T. rex is a ‘Meat Hunter’ and in a herd (which can be either matriarchal or patriarchal).