Bungie, the development studio behind the five core Halo games, has released an hour-long documentary to coincide with the studio's 20th anniversary celebrations.

The documentary relays key moments in the studio's history, including Halo's transformation from a strategy and role-playing hybrid into the system-selling franchise it became.

The Bungie team don't talk too much about their influences, but it's easy to see how they built on Wolfenstein 3D, Doom and, in early Halo prototypes, Starseige: Tribes and Planetside.

Those, too, have decendants returning in the near future. RAGE (October) comes from Id Tech of Wolfenstein, Quake and Doom fame; both Tribes: Ascend (fall) and Firefall (December) trace their lineage to Starseige, with Planetside 2 recently announced.

Though the bulk of the documentary focuses on the Halo series, the final few minutes touch on their next mystery project, with a few seconds of environmental art included.

Bungie Video Documentary "O Brave New World": www.youtu.be/OtG6-4r_qk