use Data::Dump qw/ dd /;
{
    my @blah;
    $blah[0] = [];
    $blah[0][$i] = [];
    $blah[0][$i][$j] = [];
    $blah[0][$i][$j][$k] = {};
    $blah[0][$i][$j][$k]{life} = 42;
    dd( \@blah );
}
{
    my @blah;
    $blah[0][$i][$j][$k]{life} = 42;
    dd( \@blah );
}
__END__