1
general::
Phrase(s): You and who else? [and] You and what army?
Inf. a phrase that responds to a threat by implying that the threat is a weak one. • Bill: I’m going to punch you in the nose! Bob: Yeah? You and who else? • Tom: Our team is going to slaughter your team. Bill: You and what army? • Bill: If you don’t stop doing that, I’m going to hit you. Tom: You and who else?
McGrawhill's American Idioms And Phrasal Verbs