Soldiers are the class of changelings most behaviorally similar to ponies. They are not sustained by love energy alone, but also require a diet of a carnivorous nature, though they can manage on some tubers and fruits if absolutely necessary, but they must eat meat in order to grow as fast as they do. And they do grow incredibly fast.
They are born live in small clutches, which is notoriously painful for the incubating worker, who will often be kicked out of the hive mind until the pain goes away, and must fall asleep in order to be reintegrated. From birth until the age of three, they are referred to as "grubs".
Ten years after birth, they enter a period of rapid development similar in nature to that of puberty, but somewhat more extreme, and much more disruptive to the otherwise regimented systems of the hive. Before this period, they are gender neutral, and lack any trace of a functioning reproductive system.
The soldiers become hermaphroditic, possessing functional ovaries and testes by the age of fourteen, which cannot actually produce changelings, but will create nearly perfect clones of the other parent, throwing in a few quasi random mutations so as to create genetically unique offspring.
Almost anything can reproduce with a soldier, be it griffon, pony, zebra, or timberwolf, all of which there are examples of, and possibly many more. The seemingly only thing that soldiers cannot create fertile offspring with is other changelings. My associate cannot explain why this is, only that he has seen many soldiers try to mate during their period of rowdiness.
Once fully mature, a soldier must choose between two jobs, infiltrator or spy, whereupon they lose their full independence, and become assimilated into one of two hive minds, though not entirely.