Large herd-dwelling Malamagnus feed on reeds, water lilies, and shrubs in the shallows in and around the waterways. Vulnerable to predators such as V. rexes, they tend to browse and graze along the riverbanks or in the shallows to afford carnivores less cover for ambushes and allow for a quick retreat to deep water. In the river, their size keeps them safe from all but the largest of the aquatic predators. Smaller terrestrial threats are seen off through intimidation (all adult members of the herd take part in guarding their territory aggressively from rivals or unwelcome encroachers).
In the breeding season, Malamagnus become especially aggressive and intolerant, staking out and jealously guarding territories. Large, rubbery eggs are laid in small clutches amid vegetation near the river’s edge. The young hatch well developed and are quick to join the herd, growing substantially in their first year.
Malamagnus have enormous jaws for non-mammalian synapsids of their size. While herbivorous, their impressive tusk-like teeth are employed in contests of dominance. Rivals lock jaws like battling stags and try to force one another aside. Powerful neck muscles are the key in the contest, and young males will hone their strength in mock battles.
Relationship with Dirt Turtles
Malamagnus feces are often scavenged upon by dirt turtles.