Cyclops dies within the first five to ten minutes of the movie, at the hands of Phoenix. Then, by the end of the movie, Chuck and Mags are dead. Basically, they're lining up that if a fourth movie ever does happen (which is very unlikely because this is supposed to be a trilogy), Storm will be the true leader of the X-Men, solely cause Halle wanted an expanded role. That's why I say

Halle.