Most of the changes are obviously geared towards the new expansion: the Cosmodrome map now features the new Plaguelands and Felwinter Peak areas, though they cannot be visited; a new, thus far inaccessible area has been added on Mars; SIVA clusters can be found in the "Fallen S.A.B.E.R." strike; and the opening title screen and theme music now reflects the Rise of Iron era.
The game's loot table has been adjusted, adding in the new Trespasser exotic sidearm, enabling loot drops at higher than the current maximum Light level of 335, and improving rates of legendary event reward drops.
Certain exotic weapons now have open slots for weapon ornaments; while ornaments are thus far unavailable, the weapons' ornamented appearances can be previewed in the UI.
Weapon and subclass balancing have seen sweeping changes, including a significant buff on sidearms, and nerfs on sniper rifles, high fire rate auto rifles, the Titan shoulder charge, and certain exotics.
Finally, the game's UI features a number of tweaks; most notably, the quest screen is now titled Progress, and incorporates the Record Books introduced with the Moments of Triumph feature.
Destiny: Rise of Iron launches September 20th on Xbox One and PlayStation 4.