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