In a normal game there is only one C1 Grendel in the world at a time. Grendels spawn from the Grendel Mother, on the top level of the large tree that lies next to one of the world's oceans. It only comes with sprites and body data for the adult life stage, (and the Grendel Mother only lays males by default) but there have been various third-party baby and pensioner sprites made for the C1 Grendel: Bio Storm and Don both made conversions of the C1 Grendel for Creatures 2; a Creatures 3 conversion can be found in C12DS.