Shouldn't be hard to make a chicken punishment, just set his model and strip his weapons. I doubt you'd want to give him more speed/hp and less gravity because it IS a punishment after all. Anyways, good luck.
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What am I doing these days? Well, I run my own Rust server. It's heavily modded. If you'd like to join, the ip is 167.114.101.67:28116
I also created a website called Rust Tools. It will calculate and tell you the raw amounts of resources needed to craft items.