I suspect readability isn't a big priority for you.

Here's how I'd write this, lambdas or not:

public static List<Integer> sortDescending(List<Integer> ints) {

      ints.sort(new Comparator<Integer>() {
          @Override
          public int compare(Integer o1, Integer o2) {
              if (o1.equals(o2)) {
                return 0;
              } else if (o1 < o2) {
                return 1; 
              } else { 
                return -1;
              }
          }
      });

      return ints;
  }

My personal perspective is that your use is a typical abuse which turns simple code into something unreadable and overly complex. This makes code hard to maintain and buggy. Not to mention, it's nigh impossible to step through in a debugger..