Unicorn #1 in the barn. I guess they are working on the rest. 3 plus a stand up with varied assignments is probably where this is going.The irony is that an odd stack is a slight adjustment from an old 50 front 3-4 which the NFL has used as the primary run stop front for many years. Still only 3 D-lineman. The key is a war daddy at nose that can eat up both gaps while holding point and not allowing the lineman to climb to second level which frees up the linebackers to make plays.
Legit D-lineman and shut down corners are unicorns. They are very hard to find.