The Old World is a vast and untamed placed where wild and monstrous creatures roam the dark forests and tall mountains. There are many monsters who are roughly human in appearance, though a little larger than a man, like orcs, trolls, and minotaurs, but there are also bigger and more bizarre monsters in abundance: griffons, dragons, manticores, and many more besides.
It is with these large monsters that this section of the rules is concerned. Large monsters may be ridden to battle by mighty heroes and wizards. Many of these beasts must be hand reared by their master if they are ever to accept a rider, so the great leaders of the Old World pay vast sums to adventurers who collect eggs or hatchlings from the nests of Griffons and other winged monsters. This is a dangerous profession, and for many a fatal one, but it ensures that the Emperor's Zoo in Altdorf gains fresh creatures to rear on behalf of the nobles and wizard lords of the Empire.