The Dark Below will come with new weapons, gear, missions, and story quests. It will also bring three brand new multiplayer maps, along with a six-player Raid.
The Dark Below launches on 9th December, and Bungie revealed a new EV-30 Tumbler Sparrow you can get with the DLC by either buying the Season Pass or The Dark Below before 15th January 2015.
Check out the dev diary below - you'll hear how the devs welcome the new two-way development process with the players now that the game is out. And they talk about what content players will get their hands on in the DLC. Also swords. It looks like you'll be using swords, like in that Sword of Crota mission on the Moon.