BABSON TASK

Problem-task created in 1913 by Joseph Babson.
A problem in which black promotion defenses to all possible pieces are answered by white promotions to the same piece black has promoted to. An extreme form of Allumwandlung.
The years passed, and the composers managed to present Heterodox problems with the Babson task but failed to construct Orthodox (direct-mates) problems. It has been searched for in vain for half a century. The greatest composers thought it would never be created but in 1983 a 26-year old soccer trainer from Kazan, Russia named Leonid Yarosh, a complete unknown in the problemist world composed the first of this kind.