I know it's been mentioned the Mermen from the rift have darker scales and probably handle colder water. Would the warmer waters around the Palace of Wahine and the city start making them sick? Since they're already looking not that great as it is.

What all can they find out about the rift before they enter it? So they have a little means to prepare. And...you mentioned weird rift monsters. Are those actual monsters of the rift or something else entirely?