In the rich text editor:
@Famine
In a comment:
[Famine](https://chowlings.com/user/Famine)
For Names and Avatars:
In the rich text editor:
%Famine
In a comment:
[![Famine's Avatar](https://chowlings.com/images/avatars/default.jpg)](https://chowlings.com/user/Famine) [Famine](https://chowlings.com/user/Famine)