The hcrival and hcriots srcs.rar file typically contains the raw Java code for the server's custom plugins. Developers hunt for these files to:
Keep the history of old-school Minecraft PVP alive now that many of these original networks have closed their doors. A Word of Caution
Let us know in the comments how these old-school cores compare to modern HCF setups! funkemunky/HCFCore: HCRiots's Fixed HCF Core - GitHub
Learn how these servers handled entity tracking and custom knockback.
Use the base code to build new, improved HCF experiences.
Most of this code was never officially "open source." While it's great for learning, using it for a commercial server can lead to copyright issues or community backlash. How to Use the Code
Community-shared .rar files are notorious for containing unwanted "extras." Scan everything before opening.