Mossberg SA-20 tactical. 12 gauge is very action hero, but Massad Ayoob recommends 20 for home defense, and, actually, if you can’t get the job done with a 20-gauge semi-auto you aren’t going to do better with 12.
A relative who was a small-town police chief said a shotgun is best for home defense because the pellets, unlike a solid round, are not going to go into a neighbor’s house.