Assassin's Creed Unity's Season Pass will contain two entirely new adventures: one an epilogue to the proper Unity campaign, while the other is a standalone 2.5D adventure.
The latter is described by Ubisoft as "an entirely new game" called Assassin's Creed Chronicles: China. Available in early 2015, this completely separate story puts you in the shoes of 16th century Chinese assassin, Shao Jun, as she return to Beijing to avenge her fallen brotherhood.
Shao Jun first appeared in the animated film, Assassin's Creed Embers, and she was trained by the series' earlier protagonist, Ezio Auditore. Ubisoft noted that this new game will include famous landmarks such as the Great Wall of China and the Forbidden City.
The Season Pass' other adventure, Dead Kings, is set in Saint Denis following the events of Unity. You'll still play as leading man, Arno, as he explores this new locale full of dangerous animals. Creative director Alex Amancio called Dead Kings "the darkest story we've ever told in the franchise."
In this expansion you'll be outfitted with a "Guillotine Gun" (essentially an early version of a grenade launcher with a bayonet) in addition to a lantern to explore Saint Denis' extensive underground passageways. The add-on will also include three new co-op missions back in Paris.
Those who pre-order the Unity Season Pass will receive the exclusive double-handed war axe, which can be used in the core Unity campaign and Dead Kings. The Season Pass also includes over 30 new items, such as the launch day bonus the Fleur de Lys Sword.