This tactic is similar to 4-5-1v but he changes DL/DR by DML/DMR. Other position are ok because MC can play at DMC and ST can play at AML/AMR( with yellow exclamation mark, not red ones). So, 4-3n-2w-1, 4-3n-3 work well, 3-2-2-2-1 Butterfly isn't bad choice.