No home button, Face ID, USB-C and the magnetic Apple Pencil 2. The A12X outran most Intel laptops on sale.
Released November 7, 2018 · Discontinued March 18, 2020 · From $799 (64 GB, Wi-Fi)

The Pro lost the home button and got the design iPads have used since. Flat aluminum sides, uniform bezels all the way round, Face ID that works in any orientation, and USB-C instead of Lightning, which meant an iPad could drive a display and read a camera card directly. The A12X Bionic outran most Intel laptops then on sale, which Apple claimed on stage and reviewers went away and confirmed. The second-generation Apple Pencil attaches magnetically to the side and charges there, replacing the first version's much-mocked arrangement of sticking out of the charging port. ProMotion at 120Hz makes drawing immediate. This is the machine that made the hardware case convincingly, and left the software argument unresolved for several more years.
Engadget's 2018 iPad Pro review covered both sizes, which shared the A12X, Face ID and USB-C.