  In this work, multilayer crisscross error and erasures are considered, which
affect entire rows and columns in the matrices of a list of matrices. To
measure such errors and erasures, the multi-cover metric is introduced. Several
bounds are derived, including a Singleton bound, and maximum multi-cover
distance (MMCD) codes are defined as those attaining it. Duality, puncturing
and shortening of linear MMCD codes are studied. It is shown that the dual of a
linear MMCD code is not necessarily MMCD, and those satisfying this duality
condition are defined as dually MMCD codes. Finally, some constructions of
codes in the multi-cover metric are given, including dually MMCD codes,
together with efficient decoding algorithms for them.
