Isso soa como "Nação Magi". Citando o resumo no IMDb:
Three thousand years ago in the Moonlands, the evil Shadow Magi Agram was sealed inside the planet's Core by the Core Glyph and the Dreamstones which provided its power. Now he plans to escape by using his Shadow Geysers to weaken his prison in order to bring the Moonlands under his control, and only a Magi known as the "Final Dreamer" can stop him. A young boy from Earth, Tony Jones, is summoned into the Moonlands as he is believed to be this Final Dreamer. He joins forces with the apprentice Magi, Edyn, and the Shadow Stalker, Strag, on a mission to gather the Dreamstones before Agram is set free. Using the Book of Elders, the three travel through the Moonlands while combating the forces of Agram and gaining an ever-growing collection of Dream Creatures from the Moonlands that they visit.
O "cachorro-búfalo azul com chifres laranja" pode ser esta criatura:
O trailer mostra um colar com uma gema verde transportando um garoto da Terra para outro mundo, e o uso de gemas para convocar criaturas:
O Página da Wikipedia para o programa tem uma lista de episódios, mas nada soa como os heróis lidando com um vírus, a menos que você esteja apenas se lembrando de como as Dream Creatures podem ser corrompidas nas Shadow Creatures