A new Siri watch face powered by machine learning and "Siri intelligence" comes with a top left complication that allows the wearer to receive dynamically updating notifications from a range of Apple apps and services, like Apple Home, Calendar, and Weather. The watch face offers "proactive assistance" depending on your schedule and the time of day, according to Apple, and users can rotate the Crown for more details.
The second new watch face in WatchOS 4 is a "trippy" animating kaleidoscopic face that plays on photos in a user's photo album to generate visuals when the user rotates the crown.
The last new watch face is actually a set of three Disney inspired ones to supplement the existing characters. Woody, Jessy, and Buzz from Toy Story are included, and all have animating vignettes when interacted with.