AMU: The mating, (but not checking), move may only be made by a unit, which is observed by precisely one enemy unit (including King) prior to the move. All others “mating-moves” are illegal. In this condition castling is not possible.
Reciprocal change, pure AMU defenses for the thematic mates, additional change. In the set play black’s queen twice puts a 2 nd observation on a rook, allowing the other to mate while abandoning the 8 th rank. After the key, black stops the threat by observing the white queen twice but puts a single observation on each rook, reversing the mates. (Author)
Ingenious and highly specific! Earlier compositions with this condition often used fairy pieces as well, but here the AB-BA letter contents do without. AMU – obviously a fertile and wrongly neglected condition!
Miroslav Brada invented this in the early 90s along with MAFF, OWU and maybe others.(Sounds like Franklin Roosevelt’s alphabet soup!). As for Juraj’s website, it is absolutely encylopedic! It is the site that I first found Brada’s conditions. Juraj provides an amazing service to the problem world. His >200 compositions are worth a look as well!
-c2, b1/b2 to c1/c2 saves a wP!
Ingenious and highly specific! Earlier compositions with this condition often used fairy pieces as well, but here the AB-BA letter contents do without. AMU – obviously a fertile and wrongly neglected condition!
Hubert, Awaiting 3×3 Lacny from you, using this condition! Or have you done it already? 😉
Very interesting condition! Who had introduced this and when? Can I see some earlier examples?
Several examples AMU can be found on the Juraj Lőrinc`s website: http://www.jurajlorinc.com/chess/fi_a.htm#amu
Miroslav Brada invented this in the early 90s along with MAFF, OWU and maybe others.(Sounds like Franklin Roosevelt’s alphabet soup!). As for Juraj’s website, it is absolutely encylopedic! It is the site that I first found Brada’s conditions. Juraj provides an amazing service to the problem world. His >200 compositions are worth a look as well!
By author’s request some little change is done to the diagram, -wPc2; bRc1->c2; bPc2->b2. No changes to the solution.