In the rich text editor:
@insomnicko
In a comment:
[insomnicko](https://www.worldofgaia.org/user/insomnicko)
For Names and Avatars:
In the rich text editor:
%insomnicko
In a comment:
[](https://www.worldofgaia.org/user/insomnicko) [insomnicko](https://www.worldofgaia.org/user/insomnicko)