108-Problem Solution.

Solution: 1. Be3! waiting
 1. ... Bd7/b7/a6 2. S(x)d7#
 1. ... Bxe6 2. fxe6#
 1. ... Rf7 2. Bxg5#
 1. ... Rg8/h7+ 2. S(x)h7#
 1. ... Rg6+ 2. fxg6#
 Four crosschecks are the theme of this problem.