Hello, I'm about halfway through book 2 (Deadhouse Gates), and they've introduced something called Soultaken and Divers. Not looking to have anything spoiled, but I can't quite make out exactly what they are when they show up. The Soultaken seem to be shapeshifter spellcasters? Also not sure how the Divers play into it, they just seem to be mentioned together a lot. I'm just a little bit confused, not sure if I missed something. For context, I'm at the point where Felisin and Baudin just stumbled upon this pseudo-mage merchant in the whirlwind when a Soultaken attacked their barrier, and Baudin lit himself on fire to try and kill the rats that where swarming everyone (killing Kulp).

Thanks!