So you want to join the guild Nightmare Knights?
The best way to apply is to use the applications feature on the main Tibia website and apply directly to the guild. You you should also send a letter in game to the present leader mentioning your interest to join and that you have applied to the guild on the website so we know you have already applied and are interested in joining.
Tibia is a very different game then it was when NK was founded. Guilds in particular
have changed and NK has grown to be less formal and more of a guild of old friends.
We still invite new players to join us, but most of us don't play as much.