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