Sideboarding Murmuring Mystic | tcgmode

This Dimir Terror deck made top 4 at the Spring Paupergeddon, and I'm trying to understand when you would bring in the second Murmuring Mystic. Deck: [https://mtgtop8.com/event?e=82464&d=826738&f=PAU](https://mtgtop8.com/event?e=82464&d=826738&f=PAU) Which matchups is this i...