I posted a clip on twitter recently of Zone Lock from 2 Backs and commented that it seems to be the most effective run scheme on film for 2019 that I have seen so far. The Zone Lock concept, also known as Zombie (Zone frontside, Man Backside) has been around for a while. Here is a diagram from the 2008 Destin Glazier Clinic with former Florida OL Coach, Steve Addazio.
The play is designed to go frontside but it usually cuts back behind the Sniffer. The Back must work playside first before cutting it back and he must read it because it can still hit frontside. The diagram shows how an Alley is built by the blocks of the BST and the Sniffer, making a nice cutback play the majority of the time.
Here is a recent playbook diagram:
