Etrimls are genetically engineered organisms that serve as organic computers for mortar headds. They can be used instead of fatimas to handle mortar headd systems but they are not as good. Etrimls live in a case of amniotic fluid that is permanently installed in a mortar headd. They cannot reproduce naturally. Although there are exceptions, most etrimls do not have names or personalities and thus are not considered as anything other than equipment. Dr. Chrome Ballanche and other fatima meights have created custom etrimls that are higher quality than typical etrimls. Rondo Hairline is one of Dr. Chrome Ballanche’s creations.