From Halopedia, the Halo wiki
The ilpdor were massive carnivorous amphibians that was native to Janjur Qom, the homeworld of the San'Shyuum. The ilpdor were six-legged predatory creatures that generally stayed close to water sources. The ilpdor massive body was scaled, and they had webbed, clawed feet that made it uncomfortable for the animal to walk on land. The ilpdor could not remain out of the water long. They were accompanied by a foul smell and sometimes had parasites leeching on to them. The ilpdor had sharp fangs and a long, blue tongue. The creatures were known to feed on large fish in the lakes and seas of Janjur Qom in the Reskolah region. However, overfishing in the region led to some ilpdor being unable to find food. An adult ilpdor would eat a San'Shyuum if given the opportunity. The blood of an ilpdor was green in color.
The San'Shyuum Stoic Burenn discovered a starving, young ilpdor and she managed to successfully tame it. This ilpdor was named Erb. Erb was used to transport San'Shyuum females to San'Shyuum from the Covenant that wished to bring the females back to High Charity. However, the San'Shyuum were attacked by Stoic military forces and Erb died fending them off to allow Burenn and her allies to escape.
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