Thinning out the lineup
It is pretty hilarious that this book's cover advertises that one of the characters will die, and also omits that ill-fated character's face from the heads on the same cover. It probably shouldn't have been so obvious that Thunderbird was going to get knocked off, but frankly it is a good thing. He was a terribly written character in all three issues he appeared in.
The issue opens with the X-Men plummeting towards the ground, and having a bit of a chin wag on how they're going to get out of the situation. Storm is able to help Wolverine and Nightcrawler down, while Colossus just metals up and falls without an issue. Banshee grabs Thunderbird and helps him down, with the intention of coming back for Cyclops. Then dark humor ensues, with Cyclops remarking that if Banshee doesn't hurry up he'll have to scrape Cyclops off of the mountainside with a very thin spatula. If there is more dark humor like that to be had I am excited.
Thunderbird's death scene is handled pretty well. It's not an epically memorable death, but Thunderbird wasn't exactly an epically memorable character. At least he croaks saving everyone else and takes Dr. Nefaria out in the process. That's pretty damn cool.