Horde mode

Horde stays at four players after 1.0 raised the normal co-op cap to eight. The room list, after patch 1.0.4, can filter Horde separately from Standard and Cataclysm. The same patch says a Horde run does not write the world save. Read that before you spend a night building inside the mode.

The 6 Nov challenge post is an event on top of the mode: a leaderboard, and prizes described as Steam wallet gifts sent after an email submission. That is not an in-game redeem code. Across 80 announcements I found no promo-code system at all. Console use is out for the leaderboard run. Spawn commands from the console page will not help a ranked attempt.

What actually walks at you is not itemized. The night screenshot shows a flamethrower and a crowd. I will not turn that picture into a wave chart. Base turrets from the building page are the preparation the mode assumes.