I thought that it was the target="_blank" tag, but I just tried it (as a player) on a description page and it worked.
This is the one that only GMs can use within their games:
Help-games-RuBB Code-Links:
The Anchor tag (<a>) is also available for limited use in public forums and by the GMs of games.
Evil Empryss was correct.
The Anchor tag will work on the description page, but only the GM can use it within the threads/posts. I would guess the 'description page' counts as a 'public forum'.
This message was last edited by the user at 05:28, Mon 13 June 2016.