[1][2] Magericyon occupied a different ecological niche than other amphicyonids, such as the larger Amphicyon and Ysengrinia (which had lifestyles more akin to bears) or Daphoenodon and Temnocyon of North America, which were more capable runners.

[3] As a carnivore at Cerro de los Battalones, Magericyon shared the apex predator position with two saber-toothed cat species, the leopard-sized Promegantereon ogygia and the tiger-sized Machairodus aphanistus.

Magericyon ate medium-sized prey that live in more open habitats, with the antelope Austroportax being an important food source and hipparionine horses also present in the diet.

Because the site attracted all three species as a predator trap, Magericyon must also have taken carrion or injured animals of various kinds, though its teeth show it was specialized as a hypercarnivore without the bone-cracking adaptations of many other bear-dogs.

Since its choice of prey suggests life in open country, but its legs were not designed for speed, Magericyon probably would have wasted no time in stealing a meal from any of the smaller carnivores in the region or in scavenging when the opportunity presented itself.