In the rich text editor:
@cryptidcreep
In a comment:
[cryptidcreep](https://chowlings.com/user/cryptidcreep)
For Names and Avatars:
In the rich text editor:
%cryptidcreep
In a comment:
[](https://chowlings.com/user/cryptidcreep) [cryptidcreep](https://chowlings.com/user/cryptidcreep)