A Race of tiny egotistic maniac's with delusions of grandiur. According to Visser three they are a funigal race. They possess a strange ability, they can transfer their minds to the other Helmacrons when they die. Therefore, they are never really destroyed.
They were a matriarchal society, but the Animorphs got the males to start a rebellion. The fight for the revolution continues even as their race faces intended genocide from Yeerk attacks. The Yeerks have had enough of the Helmacrons.
They execute their leaders when they are promoted so that they can never make a mistake. The fluidity of their minds may be the cause of their apperant insainity.