Tsartitan

Discovery
their discovery was quite fun as the two were discovered together, the Tsartitan minor fossil was found chasing a baby? Tsartitan primus while being chased by a Tsartitan primus, except locked in rock.

Behavior (minor)
the reason Behavior is split in two is due to the two species behaving DRASTICALLY different, at least based on fossils. future fossils showed countless scars and bite marks, all healed, from other Tsartitan minor all over their bones. they also show evidence of cannibalism and eating rotten food, turns out fossilized fur covered in fossil mold is good evidence for this. They most likely were diurnal, unlike their larger relative.

Unlike their larger cousin their teeth are sharper, showing they likely did not hunt the same things, but another thing is that their snouts are longer and thinner, so they likely did not hunt large animals.

Behavior (primus)
Primus is the hulking huge member of the family, with males having antlers in the spring. (most likely they shared this with minor but all current fossils of minor lack it either showing that a. they likely didn't have it or b. somehow we haven't found a male yet.) Their necks were made for holding INSANE amounts of weight and yanking power. Their teeth were built like a pick axe and would be used on their prey, ranging from a still unnamed ceratopsian, sauropods like deinobrontus, an unnamed stegosaur, and hadrosaurs. They were likely nocturnal as their eyes are huge and their eye rings are GIANT. A behavior that is likely, based around bears and birds of prey like owls, would protect their young when parenting