Echoed mates occur when two or more mating positions involve similar guards and blocks. Composers of the Bohemian school investigated echoed model mates thoroughly and a volume of Alain White’s Christmas series was devoted to such problems. This is an excellent example of the type.
1.Sa4 threatens 2.Rxc8 and 3.Sb6, giving two thematic variations 1…b5 2.Rxd6+ Kxd6 3.Rd7+ Kc6 4.d5 (2…Sxd6 3.Rc5) and 1…Sge7 2.Re5+ dxe5 3.Rc5+ Kd6 4.dxe5
As the black king ends up on different coloured squares the mates show a chameleon echo. The composer has added a third model mate in the variation 1…Sf6 2.Sc3+ Bxc3 3.Sg6 Kxe6 4.Sf4. Finally 1…e2 extends the threat - 2.Rxc8 e1S+ 3.Rxe1 and 4.Sb6.