Nikon D5 vs Pentax K-1

D5 has 153 AF points of which you can select 55. 99 AF points are cross-type (of which 35 are selectable). 15 AF points work with f/8 lenses (of which 9 are selectable). The autofocus works down to LV -4.

Autofocus is amazingly fast at 14 frames per second with top of the class accuracy (in tests performed by Tony Northrup it was only second to 1DX Mark II in terms of how many shots were in focus having just 6% fewer of shots be in focus).

D5 has a native ISO range of 100 to 102,400 which can be expanded from 50 to 3,280,000.

K1 has an alternate shooting mode that can significantly reduce noise and increase sharpness. It's called Pixel Shift Resolution. Once enabled it will take 4 shots moving the sensor by 1 pixel each time in order to capture all color information for each pixel instead of distributing it over 4. A visualization can be found here.

Pixel Shift Resolution shooting mode takes longer as it's taking 4 shots instead of one and requires a couple of seconds after the shots have been taken to process the images into one so it won't work for sports or action, but it's great for landscape photography.

You can potentially do night photography without a tripod by using a fast prime lens wide open with in-body image stabilization.

K-1 has a cross-tilt LCD.

It's not the camera alone; it's the camera and the lens together. Pentax's best lenses are the FA31/FA43/FA77 Limited series. There is no other camera + lens combination that can compete with the K-1 + one of the FA Limited lenses on a price/performance basis. It is not even a close competition.

Great searching through picture libraries by location.

There's an LED that shines light on rear controls, there's another one that illuminates the lens mount, and an LED that highlights the card bay and remote release port. These can be really helpful in the dark.