I'll completely agree with kings being on average more 'bitey' than some other snakes. I have 2 rescues at home that were being kept together in a too small enclosure without heating, infested with mites. In their slightly bad shape they were calm and didn't bite at all. I immediately separated them after I got them and after some time and getting them back to good health they are now (both, but the female a bit more) snakes from the depths of hell. They have an incredible feeding response, but I will only handle them with a hook as I've had the female suddenly deciding my finger is food (which is annoying with an adult king) already a couple of times.
As stated, with kings they can just switch their behavior from one moment to the next, and you just have to be wary and act quick

. Best of luck and a nippy snake is still a lot of fun

.