Here is a list of the cookies that may be set when you visit mystic.ddns.net, along with description of what they are used for and duration of them.
Session Cookie (PHPSESSID)
This cookie contains a randomly generated number and is used for authentication when logging in to or using mystic.ddns.net - this cookie is integral to the security of your account when using mystic.ddns.net and we strongly recommend that all visitors accept this cookie.
Duration: expires at end of browsing session
Homepage Cookie (homepage)
This cookie is used to remember which user is logged in, to view private 'bookmarks' when on the 'Homepage'-page. This makes it possible for the user to use the private homepage-links without logging in first! (Note: The homepage-page is not linked to anywhere but here!)
Duration: 30 days
Background Cookie (bg)
When this cookie times out, you will get another background!