Other common names include the Leste enfant, Siberian Winter Damsel, feal winterhynderke, and noordse winterjuffer. Peak strength and hardness is reached at the FeAl stoichiometric region. An early target for the attack was the FEAL block cipher. Many, even some designed by capable practitioners, have been thoroughly broken, such as FEAL. FeAl are also known - the Al rich phases show high brittleness.