Homunculus

Homunculus (Latin for "little human") are the iron defenders that players can summon.


 * Iron Defender
 * Homunculus enhancements

They can equip:
 * Companion Collars
 * Docents
 * Some effects don't take affect until the pet has been dismissed and recreated, for example, Vitality

See also Drakos's excellent Unofficial Guide to Iron Defender Pets.