The most innovative feature?

Short but sweet.
Hey, all.
In This Thread, just share what you believe to be the most innovative feature of Halo 4, and why.

In my opinion, I think Spartan Ops will pave the way for co-op experiences in games, with weekly story-related content in a similar fashion to that of a television series, ss it effectively keeps online populations high.

Player trait zones. Not an easy pick TBH but ive already come up with several gametypes/maps that are so cool due to player trait zones.