Stampede is a cooperative gamemode in the style of SVENCoop or Synergy where players work together to finish the map, be it puzzles or NPC slaughter. Although Stampede is combat-oriented and not very friendly to puzzles (especially ones that require players to pick up weapons or use the gravity gun), you can play most any maps to a degree of success.
(skip past video and screenshots)
Stampede features: classes, perks, a visually different HUD compared to most, support for almost any map, and will let clients know if the server wants to run a newer version of the content if the server lets the client know the version, as well as where to download it if they are missing the content.
Stampede also features a large amount of in-game help by simply holding F1.
Gamemode:
http://www.garrysmod.org/img/?t=dll&id=62458
Content
Facepunch Thread
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