Armstrong Feint is Ellington Feint's father.
In When Did You See Her Last?, Ellington tells Lemony Snicket about her father, that he was a naturalist who rescued baby animals and a brilliant scientist. They speculate that Armstrong may have rescued the tadpole they had found in the fishbowl. Snicket theorizes that Hangfire is kidnapping brilliant scientist like Armstrong and Cleo Knight to force them to do terrible things.
In Why Is This Night Different from All Other Nights?, it is revealed he is the villain Hangfire. After being unmasked, Snicket pushes him out of the window and into the mouth of the Bombinating Beast. The Bominating Beast swallows him, and he is presumed deceased.
- If the Bombinating Beast is the Great Unknown, then Armstrong might have survived since it is unknown what happens to those swallowed by the Great Unknown.